Answer: [tex]240\ rad/s^2[/tex]
Explanation:
Given
Length of beam [tex]l=2\ m[/tex]
mass of beam [tex]m=5\ kg[/tex]
Two forces of equal intensity acted in the opposite direction, therefore, they create a torque of magnitude
[tex]\tau =F\times l=200\times 2=400\ N.m[/tex]
Also, the beam starts rotating about its center
So, the moment of inertia of the beam is
[tex]I=\dfrac{ml^2}{12}=\dfrac{5\times 2^2}{12}\\\\I=\dfrac{5}{3}\ kg.m^2[/tex]
Torque is the product of moment of inertia and angular acceleration
[tex]\Rightarrow \tau=I\alpha\\\\\Rightarrow 400=\dfrac{5}{3}\times \alpha\\\\\Rightarrow \alpha =240\ rad/s^2[/tex]
A bullet of mass 4.00 g is fired horizontally into a wooden block of mass 1.30 kg resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.170. The bullet remains embedded in the block, which is observed to slide a distance 0.240 m along the surface before stopping. Part A What was the initial speed of the bullet
Answer:
[tex]291.67\ \text{m/s}[/tex]
Explanation:
[tex]m_1[/tex] = Mass of bullet = 4 g
[tex]m_2[/tex] = Mass of block = 1.3 kg
[tex]\mu[/tex] = Coefficient of friction = 0.17
[tex]s[/tex] = Displacement of block = 0.24 m
[tex]v_1[/tex] = Velocity of bullet
[tex]v[/tex] = Velocity of combined mass
[tex]g[/tex] = Acceleration due to gravity = [tex]9.81\ \text{m/s}^2[/tex]
The energy balance of the system is given by
[tex]\dfrac{1}{2}(m_1+m_2)v^2=\mu(m_1+m_2)gs\\\Rightarrow v=\sqrt{2\mu gs}[/tex]
As the momentum is conserved in the system we have
[tex]m_1v_1=(m_1+m_2)v\\\Rightarrow m_1v_1=(m_1+m_2)\sqrt{2\mu gs}\\\Rightarrow v_1=\dfrac{(m_1+m_2)\sqrt{2\mu gs}}{m_1}\\\Rightarrow v_1=\dfrac{(4\times 10^{-3}+1.3)\times \sqrt{2\times 0.17\times 9.81\times 0.24}}{4\times 10^{-3}}\\\Rightarrow v_1=291.67\ \text{m/s}[/tex]
The initial speed of the bullet is [tex]291.67\ \text{m/s}[/tex].
Two identical copper blocks are connected by a weightless, unstretchable cord through a frictionless pulley at the top of a thin wedge. One edge of the wedge is vertical, and the tip makes an angle of 33. The block that hangs vertically weighs 2.85 kg, and the block on the incline weighs 2.94 kg. If the two blocks do not move, what is magnitude of the force of friction on the second second block
Answer:
13.6 N
Explanation:
Since one side of the wedge is vertical and the wedge makes and angle of 33 with the horizontal, the angle between the weight of the copper block on the incline and the incline is thus 90 - 33 = 57.
Let M be the mass of the block that hangs, m be the mass of the block on the incline and T be the tension in the weightless unstretchable cord.
We assume the motion is downwards in the direction of the hanging block, M.
We now write equations of motion for each block.
So
Mg - T = Ma (1) and T - mgcos57 - F = ma where F is the frictional force on the block on the incline and a is their acceleration.
Now, since both blocks do not move, a = 0.
So, Mg - T = M(0) = 0 and T - mgcos57 - F = m(0) = 0
Mg - T = 0 (3) and T - mgcos57 - F = 0 (4)
From (3), T = Mg
Substituting T into (4), we have
T - mgcos57 - F = 0
Mg - mgcos57 - F = 0
So, Mg - mgcos57 = F
F = Mg - mgcos57
F = (M - mcos57)g
Since g = acceleration due to gravity = 9.8 m/s², and M = 2.94 kg and m = 2.85 kg.
We find F, thus
F = (2.94 kg - 2.85 kgcos57)9.8 m/s²
F = (2.94 kg - 2.85 kg × 0.5446)9.8 m/s²
F = (2.94 kg - 1.552 kg)9.8 m/s²
F = (1.388 kg)9.8 m/s²
F = 13.6024 kgm/s²
F ≅ 13.6 N
Galvani wrongly believed that the frog’s leg twitched during his experiment due to _____.
Answer:
nerves
Explanation:
I think, I maybe wrong.
Please help me with this review question.
Answer:
28.7%
Explanation:
efficiency = work output /work input × 100
As the time period of an object’s momentum change becomes longer, the force
needed to cause this change becomes _______________________.
Answer:
Speesd
Explanation:
Two ice skaters, with masses of 50 kg and 75 kg , are at the center of a 30 m -diameter circular rink. The skaters push off against each other and glide to opposite edges of the rink. Part A If the heavier skater reaches the edge in 30 s , how long does the lighter skater take to reach the edge
Answer:
t = 20 s
Explanation:
Assuming no other forces acting on the skaters when they push off against each other, and that we can neglect friction, total momentum must be conserved.The initial momentum is just zero, because both skaters are at rest.So, when both are gliding to opposite edges of the rink, at any moment, we can write the following expression:[tex]p_{f} = m_{1} * v_{1} = m_{2} * v_{2} (1)[/tex]
where m₁ = 50 kg, m₂ = 75 kg.We know that the heavier skater reaches the edge in 30 s.Since the distance from the center to any point on the edge is just half the diameter, we can find the speed of the heavier skater as follows:[tex]v_{2} = \frac{15m}{30s} = 0.5 m/s (2)[/tex]
Replacing m₁, m₂ and v₂ in (1), we can solve for the only unknown (v₁) as follows:[tex]v_{1} = \frac{m_{2}*v_{2}}{m_{1} } = \frac{75 kg*0.5m/s}{50kg} = 0.75 m/s (3)[/tex]
Since the distance to the opposite edge from the center is the same than for the heavier skater, we can find the time needed for the lighter one to reach the edge as follows:[tex]t_{1} = \frac{15m}{0.75m/s} = 20 s (4)[/tex]The ear drum vibrates when struck by sound waves and directly sends a message to the brain that is then recognized as sound
True or False
Answer:
true
Explanation:
Force of a Baseball Swing. A baseball has mass 0.153 kg . Part A If the velocity of a pitched ball has a magnitude of 44.5 m/s and the batted ball's velocity is 50.5 m/s in the opposite direction, find the magnitude of the change in momentum of the ball and of the impulse applied to it by the bat. Express your answer to three significant figures and include the appropriate units. P
Answer: 14.5 kg.m/s
Explanation:
Given
mass of baseball is [tex]m=0.153\ kg[/tex]
The initial speed of the ball is [tex]u=-44.5\ m/s[/tex]
the final speed of the ball is [tex]v=50.5\ m/s[/tex]
Impulse is given as a change in the momentum
[tex]\vec{J}=\Delta \vec{P}[/tex]
[tex]J=m(v-u)\\J=0.153(50.5-(44.5))\\J=0.153\times 95=14.535\ kg.m/s[/tex]
Change in momentum up to 3 significant figures is 14.5 kg.m/s
Impulse applied by a bat is also the same as the change in momentum
Explain how conduction, convection, and radiation occur involving a campfire
Answer:
https://wtamu.edu/~cbaird/sq/2015/02/26/when-i-sit-by-a-campfire-how-does-its-hot-air-heat-me/#:~:text=When%20you%20sit%20by%20a,It%20comes%20from%20thermal%20radiation.&text=Since%20air%20is%20a%20good,of%20pockets%20of%20heated%20fluid.
Here's a link to help you hope it helps have a good day
A 85-W lamp is connected to 100 V. What is the resistance of the lamp?
true or false
The Total electric potential due to two or more charges is equal to the algebraic sum of the potentials due to the individual charges.
Answer:
i guess the answer is false
What is the medium of the wave shown in the photograph?
A. The water
B. Kinetic energy
C. The duck
D. Gravity
Answer:
A. The water
Explanation:
i got it right on A-P-E-X
An object carries a +15.5 uC charge.
It is 0.525 m from a -7.25 uC charge.
What is the magnitude of the electric
force on the object?
Answer:
3.67 N
Explanation:
From the question given above, the following data were obtained:
Charge of 1st object (q₁) = +15.5 μC
Charge of 2nd object (q₂) = –7.25 μC
Distance apart (r) = 0.525 m
Force (F) =?
Next, we shall convert micro coulomb (μC) to coulomb (C). This can be obtained as follow:
For the 1st object
1 μC = 1×10¯⁶ C
Therefore,
15.5 μC = 15.5 × 1×10¯⁶
15.5 μC = 15.5×10¯⁶ C
For the 2nd object:
1 μC = 1×10¯⁶ C
Therefore,
–7.25 μC = –7.25 × 1×10¯⁶
–7.25 μC = –7.25×10¯⁶ C
Finally, we shall determine the force. This can be obtained as follow:
Charge of 1st object (q₁) = +15.5×10¯⁶ C
Charge of 2nd object (q₂) = –7.25×10¯⁶ C
Distance apart (r) = 0.525 m
Electrical constant (K) = 9×10⁹ Nm²/C²
Force (F) =?
F = Kq₁q₂ / r²
F = 9×10⁹ × 15.5×10¯⁶ × 7.25×10¯⁶ / 0.525²
F = 3.67 N
Therefore, the force on the object is 3.67 N
The elastic energy stored in your tendons can contribute up to 35 % of your energy needs when running. Sports scientists have studied the change in length of the knee extensor tendon in sprinters and nonathletes. They find (on average) that the sprinters' tendons stretch 41 mm , while nonathletes' stretch only 33 mm .
Hello. Your question is incomplete. However, I managed to find it completely on the internet and I realized that you forgot to mention that the question asks you for the maximum energy difference between velovistas and non-athletes, considering that the spring constant for the tendon of the two groups is equal to 33n/mm.
To make this calculation you will need to use Hooke's law, using the formula: ¹/2*K*x², where "K" will be the value of the spring constant for the tendon and "X" will be the value of the sprinter and non-athlete terms.
So for the sprinter we will have the calculation:
¹/2*33*41² -------> 0,5*33*1681 = 27736. 5 Nmm
(To facilitate the calculation, first solve the division of ¹/2 and then multiply 41 by 41, lastly, just multiply all the results.)
For the non-athlete we will have the calculation:
¹/2*33*33² -------> 0,5*33*1089 = 17968. 5 Nmm
(To facilitate the calculation, first solve the division of ¹/2 and then multiply 41 by 41, lastly, just multiply all the results.)
Now, to reach the final result, you only need to subtract the two values presented by the sprinter and the non-athlete.
27736.5 - 17968.5 = 9768 Nmm
Students are asked to design an experiment to confirm that the pressure and volume of an ideal gas are inversely proportional. They use a cylinder containing an ideal gas that has a plunger equipped with a pressure sensor. They perform several trials, and in each trial they start with the gas at the same initial pressure and volume. The students then quickly push the plunger so that the gas achieves a different final pressure and volume. After analyzing their results, they determine that the final pressures and volumes do not follow an inversely proportional relationship. Which of the following refinements to the procedure would show the inverse proportionality between pressure and volume?
A. Compress the gas slowly so that the temperature remains constant.
B. Perform more trials to obtain more data points.
C. Discard data points that do not show inverse proportionality between pressure and volume.
D. Compress the plunger even faster so that the compression is effectively instantaneous.
Answer:
the answers the correct one is A
Explanation:
Let's analyze the situation, the expression for ideal gases is
PV = n R T
in this case n is the number of moles of the gas remains constant, so we see that there is a relationship between volume, pressure and temperature.
For the experiment we are conducting we must ensure that the temperature remains constant, one way to achieve this is by placing a small thermometer on the surface of the cylinder.
By rapidly compressing part of the work done, it is converted into internal energy of the gas molecules, and from there it is transformed into its temperature. One way to reduce this effect is to COMPRESS SLOWLY and thus keep the temperature constant.
This method of allowing to check
P V = cte
when checking the answers the correct one is A
The photograph shows part of the Great Plains of North America. How do
plains form?
A. Magma rises at a divergent plate boundary.
B. Tectonic movements make folds and faults in the crust.
C. Continental plates slip past each other at a transform boundary.
D. Water, wind, or glaciers either remove or deposit crust.
SUBMIT
2 PREVIOUS
Answer:
Some plains form as ice and water erodes, or wears away, the dirt and rock on higher land. Water and ice carry the bits of dirt, rock, and other material, called sediment, down hillsides to be deposited elsewhere. As layer upon layer of this sediment is laid down, plains form. Volcanic activity can also form plains.
Which of the following correctly explains the difference between sound and light?
A.Sound is a longitudinal wave that does not require a medium through which to travel, and light is a transverse wave that does require a medium.
B.Sound is a longitudinal wave that requires a medium through which to travel, and light is a transverse wave that does not require a medium.
C.Sound is a transverse wave that requires a medium through which to travel, and light is a longitudinal wave that does not require a medium.
D.Sound is a transverse wave that does not require a medium through which to travel, and light is a longitudinal wave that does require a medium.
Answer: i think the answer is C
Explanation:
A box having a weight of 8 lb is moving around in a circle of radius rA = 2 ft with a speed of (vA)1 = 5 ft/s while connected to the end of a rope. If the rope is pulled inward with a constant speed of vr = 4 ft/s, determine the speed of the box at the instant rB = 1 ft. How much work is done after pulling in the rope from A to B? Neglect friction and the size of the box
Answer:
W = 1.875 J
Explanation:
For this exercise let's use the relationship between work and kinetic energy
W = ΔK
The kinetic energy of rotational motion is
K₀ = ½ I w²
we can assume that the box is small, so it can be treated as a point object, with moment of inertia
I = m rₐ²
angular and linear velocity are related
v = w r
w = v / r
we substitute in the equation, for point A
K₀ = ½ (m rₐ²) (v / rₐ)²
K₀ = ½ m v²
For the final point B, as the system is isolated the angular momentum is conserved
initial L₀ = Io wo
final L_f = I_f w_f
L₀ = L_f
I₀ w₀ = I_f w_f
(m rₐ²) w₀ = (m [tex]r_{b} ^2[/tex]) w_f
w_f = (rₐ/r_b)² w₀
with this value we find the final kinetic energy
K_f = ½ I_f w_f²
K_f = ½ (m [tex]r_{b}^2[/tex]) ( (rₐ / r_b)² w₀) ²
K_f = ½ m [tex]\frac{r_a^4}{r_b^2} \ w_o^2[/tex]
we substitute in the realcion of work
W = K_f - K₀
W = ½ m [tex]( \( \frac {r_a^2 }{r_b} )^2[/tex] w₀² - ½ m v²
W = ½ m [tex]\frac{r_a^4}{r_b^2} ( \frac{v}{r_a} ) ^2[/tex] - ½ m v²
W = ½ m [tex]\frac{r_a^2}{r_b^2} \ v^2[/tex] - ½ m v2
W = ½ m v² (([tex]( \ (\frac{r_a}{r_b})^2 -1)[/tex]
let's calculate
W = ½ ( [tex]\frac{8}{32}[/tex] ) 5 ((2/1)² -1)
W = 0.625 (3)
W = 1.875 J
A 72.9-kg base runner begins his slide into second base when moving at a speed of 4.02 m/s. The coefficient of friction between his clothes and Earth is 0.701. He slides so that his speed is zero just as he reaches the base. (a)How much mechanical energy is lost due to friction acting on the runner
Answer:
-589.05 J
Explanation:
Using work-kinetic energy theorem, the work done by friction = kinetic energy change of the base runner
So, W = ΔK
W = 1/2m(v₁² - v₀²) where m = mass of base runner = 72.9 kg, v₀ = initial speed of base runner = 4.02 m/s and v₁ = final speed of base runner = 0 m/s(since he stops as he reaches home base)
So, substituting the values of the variables into the equation, we have
W = 1/2m(v₁² - v₀²)
W = 1/2 × 72.9 kg((0 m/s)² - (4.02 m/s)²)
W = 1/2 × 72.9 kg(0 m²/s² - 16.1604 m²/s²)
W = 1/2 × 72.9 kg(-16.1604 m²/s²)
W = 1/2 × (-1178.09316 kgm²/s²)
W = -589.04658 kgm²/s²
W = -589.047 J
W ≅ -589.05 J
Tony ran 600 meters in 60 seconds. What was Tony's speed during the
race?
Two identical loudspeakers are driven in phase by the same amplifier. The speakers are positioned a distance of 3.2 m apart. A person stands 5.0 m away from one speaker and 6.2 m away from the other. Calculate the second lowest frequency that results in destructive interference at the point where the person is standing. Assume the speed of sound to be 330 m/ s. A) 183 Hz B) 275 Hz C) 413 Hz D) 137 Hz E) 550 Hz
Answer:
C) 413 Hz
Explanation:
For destructive interference, the path difference ΔL = (n + 1/2)λ where ΔL = L₂ - L₁ where L₁ = person's distance from one speaker (the closer one) = 5.0m and L₂ = person's distance from other speaker (the farther one) = 6.2 m and λ = wavelength = v/f where v = speed of sound = 330 m/s and f = frequency
So, ΔL = (n + 1/2)λ
L₂ - L₁ = (n + 1/2)v/f
f = (n + 1/2)v/(L₂ - L₁)
At the second lowest frequency that results in destructive interference at the point where the person is standing, n = 1.
So,
f = (1 + 1/2)v/(L₂ - L₁)
f = 3v/2(L₂ - L₁)
Substituting the values of the variables into the equation, we have
f = 3v/2(L₂ - L₁)
f = 3(330 m/s)/2(6.2 m - 5.0 m)
f = 3(330 m/s)/2(1.2 m)
f = 990 m/s ÷ 2.4 m)
f = 412.5 Hz
f ≅ 413 Hz
What causes the Coriolis effect?
A
The sun's position relative to Earth
B.
Earth's orbit around the sun
с
Moon phases
D
Earth's rotation
Two protons (each with q = 1.60 x 10-19)
in a nucleus are located 1.00 x 10-15 m
apart. How much electric force do they
exert on each other?
[?] N.
Answer:
230.4 N
Explanation:
From the question given above, the following data were obtained:
Charge (q) of each protons = 1.6×10¯¹⁹ C
Distance apart (r) = 1×10¯¹⁵ m
Force (F) =?
NOTE: Electric constant (K) = 9×10⁹ Nm²/C²
The force exerted can be obtained as follow:
F = Kq₁q₂ / r²
F = 9×10⁹ × (1.6×10¯¹⁹)² / (1×10¯¹⁵)²
F = 9×10⁹ × 2.56×10¯³⁸ / 1×10¯³⁰
F = 2.304×10¯²⁸ / 1×10¯³⁰
F = 230.4 N
Therefore, the force exerted is 230.4 N
Answer:
230.4
Explanation:
acellus
The following statements address the science behind the pulley system illustrated:
A. The pulleys increase the entropy of the system.
B. The force applied to the rope is less than the force needed to lift the object.
C. The pulleys help generate as much energy as possible.
D. The pulleys multiply energy input, resulting in more energy output.
E. The pulleys generate no thermal energy.
Which of these statements is/are true?
i. Statements A and B
ii. Statements D and E
iii. Only statement C
iv. All of the statements
Answer:
i. Statements A and B
Explanation:
Sana nakatulong
hhhep faaast plssssss
Answer:
false
Explanation:
I am in need of points sorry
4) Which statement about teamwork is not true?
A) Team members should not have to make personal sacrifices for the success of the team.
B) To be successful, all team members need to agree about how to achieve the goal.
C) To achieve agreement, teams must be able to communicate and negotiate.
D) Team members need to be ready to resolve conflicts in an open and honest way
Answer: A) Team should not have to make personal sacrifices for the success of the team.
Explanation:
A cars engine can deliver 300,000 watts of power to its wheels.
A. If the engine acts for 6 seconds, what is the work done on the car?
B. If the car travels 0.25 miles, what force acted on the car?
C.If the cars mass is 1200 kg, what is the acceleration of the car?
Answer:
A. 1,800,000 J
B. 4473.87 N
C. 3.728 m/s²
Heeelp me faaast plllsss
Answer:
the first one
Explanation:
cartridge fuse
Melvina has a mass of 70 kg and is about to jump from the window ledge of a burning building.
The ledge is 80 m above the ground. What is Melvina's potential energy?
Melvina's potential energy is 54,880 Joules.
To calculate Melvina's potential energy, we need to use the formula for gravitational potential energy:
Potential energy = mass × gravitational acceleration × height
Potential energy is a measure of the energy an object possesses due to its position relative to other objects. In this case, Melvina's potential energy is a result of her height above the ground. As she stands on the ledge of the burning building, her potential energy is stored and can be converted into other forms of energy if she were to jump or fall. The potential energy will decrease as she descends, and it will be converted into kinetic energy (energy of motion).
Given that Melvina has a mass of 70 kg and the ledge is 80 m above the ground, we can substitute the values into the formula:
Potential energy = 70 kg × 9.8 m/s² × 80 m
Calculating this, we find:
Potential energy = 54,880 Joules
For such more questions on energy
https://brainly.com/question/30369234
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A 5kg cart moving to the right with a velocity of 16 m/s collides with a concrete wall and
rebounds with a velocity of 22 m/s. Is the change in momentum of the cart
Explanation:
mass, m = 5kg
initial velocity, u = 16m/s
final velocuty, v = -22m/s
change in momentum, ∆p = ?
∆p = m (v-u)
5(-22-16)
5(38)
∆p = 190kgm/s
check the calculations!