Answer:
0.3333
Explanation:
Acceleration = change in velocity/time
a = 20 m/s / 60 m/s
a = 0.3333 m/s^2
A lens with a focal length of 20 cmcm is placed 45 cmcm in front of a lens with a focal length of 5.0 cm. How far from the second lens is the final image of an object infinitely far from the first lens?
Answer:
25
Explanation:
Communication satellite use__sent by a transmitting station to transmit signals over long distances A microwaves B polar waves C light D radio waves
D: radio waves
Explanation:
radio wves are use to carry satellite signals
A 35 kg child slides down a playground slide at a constant speed. The slide has a height of 3.8 m and is 8.0 m long. Find the magnitude of the kinetic friction force acting on the child.
Answer:
The magnitude of the kinetic frictional force acting on the child is 162.93 N
Explanation:
Given;
mass of the child, m = 35 kg
height of the slide, h = 3.8 m
length of the slide, d = 8.0 m
The change in thermal energy associated with the kinetic frictional force is calculated as follows;
[tex]\Delta E_{th} + \Delta K.E + \Delta U = 0\\\\\Delta E_{th} + (\frac{1}{2} mv_f^2 - \frac{1}{2} mv_i^2) + (mgh_f - mgh_i) =0\\\\since \ the \ speed \ is \ constant, \ v_f = v_i \ and \ \Delta K.E = 0\\\\Also, \ final \ height \ , h _f= 0\\\\\Delta E_{th} - mgh_i = 0\\\\\Delta E_{th} = mgh_i\\\\\Delta E_{th} = 35 \times9.8 \times 3.8\\\\\Delta E_{th} = 1303.4 \ J[/tex]
The magnitude of the kinetic frictional force that produced this thermal energy is calculated from the work done by frictional force;
[tex]\Delta E_{th} = F \times d\\\\F = \frac{\Delta E_{th} }{d} \\\\F = \frac{1303.4}{8} \\\\F = 162.93 \ N[/tex]
Therefore, the magnitude of the kinetic frictional force acting on the child is 162.93 N
A bare helium nucleus has two positive charges and a mass of 6.64 ✕ 10−27 kg. (a) Calculate its kinetic energy in joules at 3.60% of the speed of light.
Answer:
the kinetic energy of the particle is 3.872 x 10⁻¹³ J
Explanation:
Given;
mass of helium, m = 6.64 x 10⁻²⁷ kg
speed of light, c = 3 x 10⁸ m/s
3.6% of speed of light, c = 0.036 x 3 x 10⁸ m/s = 1.08 x 10⁷ m/s
The kinetic energy of the particle is calculated as;
K.E = ¹/₂mc²
K.E = ¹/₂ x (6.64 x 10⁻²⁷) x (1.08 x 10⁷)²
K.E = 3.872 x 10⁻¹³ J
Therefore, the kinetic energy of the particle is 3.872 x 10⁻¹³ J
calculate the correct fuse that should be used for a 230V,1KW electric hair dryer.
Answer: 4 A
Explanation:
Given
Voltage [tex]V=230\ V[/tex]
Power [tex]P=1\ kW[/tex]
Power is given by [tex]P=VI\\[/tex]
Insert the values
[tex]\Rightarrow 1000=230\times I\\\\\Rightarrow I=\dfrac{1000}{230}\\\\\Rightarrow I=3.84\ A[/tex]
The rating of fuse is slightly higher than the normal operating conditions. Therefore, a 4 A fuse should be used here.
figure 2. sketch of bar and magnetic field lines observations PLEASE HELPPPP
A Michelson interferometer operating at a 600nm wavelength has a 2.02-cm-long glass cell in one arm. To begin, the air is pumped out of the cell and mirror M2 is adjusted to produce a bright spot at the center of the interference pattern. Then a valve is opened and air is slowly admitted into the cell. The index of refraction of air at 1.00 atm pressure is 1.00028.
How many bright-dark-bright fringe shifts are observed as the cell fills with air?
Answer:
19
Explanation:
Given that:
wavelength = 600 nm
Distance (d) = 2.02 cm = 2.02 × 10⁻² m
refraction index of air (n) = 1.00028
Pressure = 1.00 atm
∴
The number of bright-dark-bright fringe shifts can be determined by using the formula:
[tex]\Delta m = \dfrac{2d}{\lambda} (n -1 ) \\ \\ \Delta m = \dfrac{2\times2.02 \times 10^{-2}}{600\times 10^{-9}} (1.00028 -1 ) \\ \\ \Delta m = 67333.33 \times 10^{-5}(1.00028 -1) \\ \\ \Delta m = 67333.33 \times 10^{-5}(2.8\times 10^{-4}) \\ \\ \Delta m = 18.853 \\ \\ \mathbf{\Delta m = 19}[/tex]
Select the correct answer.
What happens when two polarizers are placed in a straight line, one behind the other?
A.
They allow light to pass only if they are polarized in exactly the same direction.
B.
They block all light if they are polarized in exactly the same direction.
C.
They allow light to pass only if their directions of polarizations are exactly 90° apart.
D.
They block all light if their directions of polarizations are exactly 90° apart.
E.
They block all light if their directions of polarizations are either exactly the same or exactly 90° apart.
Answer:
C. They allow light to pass only if their directions of polarizations are exactly 90° apart.
Explanation:
If two polarizers are placed in a straight line, one behind the other, they allow light to pass only if their directions of polarizations are exactly 90° apart.
A wave has a frequency of 87.00 Hz and has a wavelength of 74.62 m. What is its
velocity?
Answer:
v = 6491.94 m/s
Explanation:
We are given;
Frequency; f = 87 Hz
Wavelength;λ = 74.62 m
Formula for velocity(v) of waves from the wave equation is;
v = fλ
Thus;
v = 87 × 74.62
v = 6491.94 m/s
A 7.5-kg rock and a 8.9 × 10-4-kg pebble are held near the surface of the earth. (a) Determine the magnitude of the gravitational force exerted on each by the earth. (b) Calculate the magnitude of the acceleration of each object when released.
Answer:
F' = 73.7 N
F = 8.749×10⁻³ N
a' = a = 9.83 m/s²
Explanation:
(a)
For the rock
Applying
F' = Gm'm/r²................... Equation 1
Where F = magnitude of the gravitational force on the rock, G = Gravitational constant, m' = mass of the rock, m = mass of the earth, r = radius of the earth.
From the question,
Given: m' = 7.5 kg
Constant: m = 5.98×10²⁴ kg, G = 6.67×10⁻¹¹ Nm²/kg², r = 6.37×10⁶ m
Substitute these values into equation 1
F' = 6.67×10⁻¹¹ (7.5)(5.98×10²⁴)/(6.37×10⁶)²
F' = 7.37×10¹ N
F' = 73.7 N
Also, For the pebble,
F = GMm/r².............. Equation 2
Where M = mass of the pebble, F = Gravitational force exerted on the pebble by the earth
Given: M = 8.9×10⁻⁴ kg,
Substitute into equation 2
F = 6.67×10⁻¹¹(8.9×10⁻⁴)(5.98×10²⁴)/(6.37×10⁶)²
F = 8.749×10⁻³ N
(b)
For the rock,
a' = F'/m'
Where a' = magnitude of the acceleration of the rock
a' = 73.7/7.5
a' = 9.83 m/s²
For the pebble,
a = F/M
Where a = acceleration of the pebble
a = (8.749×10⁻³)/(8.9×10⁻⁴)
a = 9.83 m/s²
A hammer has a mass of 1 kg. What is its weight (i) on Earth (ii) on the
Moon (iii) in outer space
Given mass= 1kg
Weight on earth = mg(gravity of earth) = 9.8N
weight on moon = mg(gravity of moon)= 1.62N
weight on outer space mg(gravity outer space = 0) = 0N
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 40 mm, while nonathletes' stretch only 32 mm. The spring constant for the tendon is the same for both groups, 32 N/mm. What is the difference in maximum stored energy between the sprinters and the nonathlethes?
Answer:
Explanation:
From the given information:
The difference in the maximum energy stored is can be determined by finding the difference in the maximum stored energy in the sprinters and that of the non-athlete:
[tex]\Delta U = \dfrac{1}{2}k(x_2^2 - x_1^2)[/tex]
[tex]\Delta U = \dfrac{1}{2} (32 \ N/mm) (\dfrac{1 \ mm}{10^{-3} \ m}) ((40\times 10^{-3})^2 - (32\times 10^{-3})^2)[/tex]
[tex]\Delta U =16000 \times (5.76\times 10^{-4})[/tex]
[tex]\mathbf{\Delta U =9.216\ J}[/tex]
Cual es l diferencia entre ruido y sonido
Answer:
E.l soni.do es un.a sensac.ión, en el órg.ano del oído, prod.ucida por el movimie/nto ondu>latorio de un m/edio elástico (normal/mente el aire), debi.do a ra.pidísimos ca/mbios de pre.sión, generado/s por el movimiento vibrat.orio d.e un cuerpo sonoro. ... /El ruido se consid/era a to/do sonid.o / o no de.seado.
Explanation:
A ball is thrown horizontally from the top of a building 59 m high. The ball strikes the ground at a point 65 m horizontally away from and below the point of release. What is the speed of the ball just before it strikes the ground
Answer:
Explanation:
We are looking for final velocity. Since the ball is thrown horizontally, there is no upwards velocity, so the y dimension here is only useful to us for finding how long the ball was in the air. In the y dimension, here's what we know:
a = -9.8 m/s/s
Δx = -59 m
[tex]v_0=0[/tex] (again, initial upwards velocity is 0 because the ball was thrown horizontally)
We can put all that together in the equation:
Δx = [tex]v_0t+\frac{1}{2}at^2[/tex] and filling in:
[tex]-59=0t+\frac{1}{2}(-9.8)t^2[/tex] which simplifies to
[tex]-59=\frac{1}{2}(-9.8)t^2[/tex] and solving for t:
[tex]t=\sqrt{\frac{2(-59)}{-9.8} }[/tex] and
t = 3.5 sec
Now we can use that time in the d = rt equation, which is all we need for the horizontal dimension (I'll show you why in just a second). In the horizontal dimension, here's what we know:
a = 0 m/s/s
Δx = 65 m
t = 3.5 sec
Putting that all together in our one-dimensional equation for displacement:
Δx = [tex]v_0t+\frac{1}{2}at^2[/tex] and acceleration is 0, we can simplify that down to
Δx = [tex]v_0t[/tex] which is the exact same thing as d = rt where r is the velocity we are looking for. Filling in:
65 = v(3.5) so
v = 18.6 m/s
That's the velocity with which the ball strikes the ground.
Identify each statement as an example of melting or sublimation,
lodide produces fumes when heated.
Melting
Sublimation
An iceberg turns to ocean water.
Candle wax turns to liquid when hot.
"Fog" is created from dry ice.
1st is sublimation
2and is melting
3red is melting
4th is sublimation
sublimation is just "skipping" the liquid phase / state
A 45.00 kg person in a 43.00 kg cart is coasting with a speed of 19 m/s before it goes up a hill. there is no friction, what is the maximum vertical height the person in the cart can reach?
Answer:
the maximum vertical height the person in the cart can reach is 18.42 m
Explanation:
Given;
mass of the person in cart, m₁ = 45 kg
mass of the cart, m₂ = 43 kg
acceleration due to gravity, g = 9.8 m/s²
final speed of the cart before it goes up the hill, v = 19 m/s
Apply the principle of conservation of energy;
[tex]mgh_{max} = \frac{1}{2}mv^2_{max}\\\\ gh_{max} = \frac{1}{2}v^2_{max}\\\\h_{max} = \frac{v^2_{max}}{2g} \\\\h_{max} =\frac{(19)^2}{2\times 9.8} \\\\h_{max} = 18.42 \ m[/tex]
Therefore, the maximum vertical height the person in the cart can reach is 18.42 m
an artificial satellite is moving in a circular orbit of radius 36000 kilometre calculate its speed if it takes 24 hours to revolve around the earth
Explanation:
9420 km/hr is the correct answer
Hope this helps...☺
Lighting is the movement of?
Explanation:
Movement:refers to the changing in the lights whether it be a change in intensity, color or direction of origin.
PLEASE HELP ME WITH THIS ONE QUESTION
The color orange has a wavelength of 590 nm. What is the energy of an orange photon? (h = 6.626 x 10^-19, 1 eV = 1.6 x 10^-19 J)
A) 2.81 eV
B) 3.89 eV
C) 2.10 eV
D) 2.78 eV
k = [tex] \dfrac{ (\dfrac{h}{ \lambda} )^{2} }{2m} [/tex]
k = (6.626×10-¹⁹/590 × 10-⁹ )^{2} /2 × 1.673 × 10-²⁷
k = (1.12 × 10-³⁰)^2/3.346×10-²⁷
k = 1.25 × 10-⁶⁰ /3.346×10-²⁷
k = 0
ldk why, my answer is coming this :(
write the adverbs use in sentences no.1-5 ty
Answer:
ok I have written in your face check it out fast don't have time see see see fast
a mass of air occupied 150 cm3 at 20°c and 760 mmhg pressure. calculate it volume when heated to 100°c and constant pressure
Answer:
191 cm³
Explanation:
We'll begin by converting celsius temperature to Kelvin temperature. This can be obtained as follow:
T(K) = T(°C) + 273
Initial temperature (T₁) = 20 °C
Initial temperature (T₁) = 20 °C + 273
Initial temperature (T₁) = 293 K
Final temperature (T₂) = 100 °C
Final temperature (T₂) = 100 °C + 273
Final temperature (T₂) = 373 K
Finally, we shall determine the final volume of the air. This can be obtained as follow:
Initial volume (V₁) = 150 cm³
Initial temperature (T₁) = 293 K
Final temperature (T₂) = 373 K
Pressure = constant
Final volume (V₂) =?
V₁/T₁ = V₂/T₂
150 / 293 = V₂ / 373
Cross multiply
293 × V₂ = 150 × 373
293 × V₂ = 55950
Divide both side by 293
V₂ = 55950 / 293
V₂ ≈ 191 cm³
Thus, the final volume of the air is 191 cm³
Calculate the battery voltage to send 2.5 A of current through a light bulb with 3.6 ohms of resistance
Answer:
9 volts
Explanation:
[tex]v = i \times r \\ v = 2 .5 \times 3.6 \\ v = 9[/tex]
Who Knows?
Thank You
Answer:
Use below table to read the color codes.
how much heat energy is required to vaporize a 1 g ice cube at 0 C. The heat of fusion of ice is 3.36 x 10^5 J/kg . The heat of vaporization of water is 2.26 x 10^6 J/Kg. ( specific heat of water = 4200 J/Kg C )
Answer:
Q = M * (Cf + C * 100 + Cv)
Cf and Cf are heats of fusion and vaporization and C is the heat required to heat mass M of water 1 deg
Q = .001 kg ( 3.36 * E5 + 100 deg * 4200 + 2.26 * E6) J
Q = .001 kg ( 3.36 J / kg + 4.2 J / kg + 22.6 J /kg) * 10E5
Q = .001 kg * 30.2 * 10E5 J / kg = 3020 J
Mention & Instrument used to measure
the mass of the body.
Answer:
a scale is used to measure the mass of the body
Study the position-time graph for a bicycle. Which statement is supported by the graph? Position vs Time O The bicycle has speed but not velocity. O The bicycle is moving at a constant velocity. O The bicycle has a displacement of 3 m. O The bicycle is not in motion. 3 Position (m) 0 1 2 3 4 5 Time (s) Next Submit Save and Exit Mark this and return tViewers/AssessmentViewer/Activit. 0 M M
Answer:
D) The bicycle is not in motion.
Explanation:
Study the position-time graph for a bicycle.
Which statement is supported by the graph?
A) The bicycle has speed but not velocity.
B) The bicycle is moving at a constant velocity.
C) The bicycle has a displacement of 3 m.
D) The bicycle is not in motion.
Solution:
Velocity is the time rate of change of displacement. It is the ratio of displacement to time taken.
Speed is the time rate of change of distance. It is the ratio of distance to time taken.
From the position-time graph, we can see that the bicycle has a constant positon of 3 m for the whole of the time. That is the position remains 3 m even as the time changes. Therefore, we can conclude that the bicycle is not in motion.
From the position-time data provided, it can concluded that the bicycle is not in motion.
MotionMotion of a body involves a change in the position of that body with time.
A body in motion is constantly changing position or orientation as time passes.
The body may move with constant velocity/speed or changes in its velocity.
A position-time graph provides information about the motion of a body.
From the data provided:
At time 0, the bicycle is at position 3At time 1, the bicycle is at position 3At time 2, the bicycle is at position 3At time 3, the bicycle is at position 3At time 4, the bicycle is at position 3At time 5, the bicycle is at position 3The position of the bicycle remains the same for all time intervals.
Therefore, from the position-time data provided, it can concluded that the bicycle is not in motion.
Learn more about motion and position-time graph at: https://brainly.com/question/2356782
Hot water is added to three times its water at 10 degree Celsius and the resulting temperature at 20 degree Celsius. what is the initial temperature
what are 2 ways that we can express to show our connection to our culture
Answer:
Food, clothes, language, and belief
who is corazon aquino?
Answer:
Maria Corazon Sumulong Cojuangco Aquino, popularly known as Cory Aquino, was a Filipino politician who served as the 11th President of the Philippines, the first woman to hold that office.
Answer:
Former President of the Philippines
Explanation:
A motorist travels due North at 90 km/h for 2 hours. She changes direction and travels West at 60 km/for 1 hour.
a) Calculate the average speed of the motorist [4]
b) Calculate the average velocity of the motorist.
Answer:
a. 50km/hr.
b. 10km/hr
Explanation:
Average speed, which is calculated by dividing the total distance travelled by the time interval as follows:
Average speed = total distance travelled ÷ time
Average velocity is calculated by dividing the total displacement by the time interval as follows:
Average velocity = change in displacement (∆x) ÷ time (t)
According to this question, a motorist travels due North at 90 km/h for 2 hours. She then changes direction and travels West at 60 km/for 1 hour.
Total distance of this journey is 90 + 60 = 150
Total time taken = 1 + 2 = 3hours
Average speed = 150/3
= 50km/hr.
b.) Average velocity = x2 - x1/t
Average velocity = 90 - 60/3
= 30/3
= 10km/hr