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Answer:c i.e. rifle has lots of mass

Explanation:It's because we know that the force of recoiling is same. But since the mass of rifle is very much greater than that of the bullet, it's balanced by the less speed of the recoiling of the rifle.

Answer:

B. Current in the circuit is 5.

Ci. Voltage across 7.2 Ω (R₁) is 36 V

Cii. Voltage across 6.2 Ω (R₂) is 31 V

Ciii. Voltage across 8.6 Ω (R₃) is 43 V

Explanation:

We'll begin by calculating the number equivalent resistance in the circuit. This can be obtained as follow:

Resistor 1 (R₁) = 7.2 Ω

Resistor 2 (R₂) = 6.2 Ω

Resistor 3 (R₃) = 8.6 Ω

Equivalent Resistance (R) =?

Since the resistors are in series connection, the equivalent resistance can be obtained as follow:

R = R₁ + R₂ + R₃

R = 7.2 + 6.2 + 8.6

R = 22 Ω

B. Determination of the current.

Voltage (V) = 110 V

Resistance (R) = 22 Ω

Current (I) =?

V = IR

110 = I × 22

Divide both side by 22

I = 110 / 22

I = 5 A

Therefore, the current in the circuit is 5.

Ci. Determination of the voltage across 7.2 Ω (R₁)

Resistor 1 (R₁) = 7.2 Ω

Current (I) = 5 A

Voltage 1 (V₁) =?

V₁ = IR₁

V₁ = 5 × 7.2

V₁ = 36 V

Therefore, the voltage across 7.2 Ω (R₁) is 36 V

Bii. Determination of the voltage across 6.2 Ω (R₂)

Resistor 2 (R₂) = 6.2 Ω

Current (I) = 5 A

Voltage 2 (V₂) =?

V₂ = IR₂

V₂ = 5 × 6.2

V₂ = 31 V

Therefore, the voltage across 6.2 Ω (R₂) is 31 V

Ciii. Determination of the voltage across 8.6 Ω (R₃)

Resistor 3 (R₃) = 8.6 Ω

Current (I) = 5 A

Voltage 3 (V₃) =?

V₃ = IR₃

V₃ = 5 × 8.6

V₃ = 31 V

Therefore, the voltage across 8.6 Ω (R₃) is 43 V

Answer:

The answer is B

Explanation:

Only things that are moving have kinetic energy, therefore B is the only correct answer

The thermal energy transfer will occur by convection from the aluminium to the beaker.

Thermal energy can be defined as the energy held in a system that is accountable for the overall temperature of the system.

Conduction is the process by which heat energy is transferred from one material or substance to another.

Convection is the transfer of heat in the fluid medium. e.g when a fluid is heated, heat energy is transferred into the fluid which causes a rise in the temperature of the fluid.

Since water is a fluid medium, the thermal energy transfer will occur by convection from the aluminium to the beaker.

Learn more about thermal energy here:

https://brainly.com/question/7541718

Answer:

Answer is letter B

Answer:  THE CORRECT ANSWER IS :  The partiles that make up material B are more closely packed together than the partiles that make up material A

Explanation:     I TOOK THE TEST    apex

The answer is chemical

Answer:

A. 80 N

Explanation:

Since the uniform plank is pivoted at its center at an angle of 30 to the vertical, then it is 90° - 30° = 60° to the horizontal.

Let L be the length of the plank = 4 m, the perpendicular distance of the 4 kg mass form the pivot point is Lcos60°/2. Then the moment of the 4 kg mass about its pivot point is mgLcos60/2 where m = mass = 4 kg and g = acceleration due to gravity = 10 m/s²

Let F be the force applied at 0.5 m from the pivot point. The perpendicular distance of F from the pivot point is 0.5cos60°. Thus the moment of this force about the pivot point is F × 0.5cos60° = 0.5Fcos60°

Since both moments are the same for equilibrium,

mgLcos60/2 = 0.5Fcos60°

F = mgL/(2 × 0.5 m)

F = 4 kg × 10 m/s² × 4 m/1 m

F = 80 kgm/s²

F = 80 N

Answer:

I got 2508 J

Explanation:

q=mct

125-95

= 30 * 4.18 * 20

= 2508

Answer:

Fossils are the remains of an ancient organism or the traces of activity of such an organism. There are two types of fossils: body fossils and trace fossils. Body fossils include preserved remains of an organism (i.e. freezing, drying, petrification, permineralization, bacteria and algea).

Answer:

A work is done because the object moved

B no work is done because the donkey didnt move

Explanation:

Answer: A roller coaster does not have an engine to generate energy. The climb up the first hill is accomplished by a lift or cable that pulls the train up. This builds up a supply of potential energy that will be used to go down the hill as the train is pulled by gravity

Hope this helps! Good luck with future homework and exams!

Answer:

simltinoues divide two eqn El÷E2 Kq\ r^2\kq \2r^2 then you get it 7.5 N\c the answer is A

Answer:

d

Explanation:

we simplify the circuit into groups to obtain a complete circuit I.e series and parallel circuit

Answer:

c) time

Explanation:

time is a fundamental quantity from which other quantities are derived

Answer:

540 J

Explanation:

U at top equals to K at bottom if it's an isolated system therefore U at top is equals to 540 J so we can assume that at 0m U=0 (mgh) therefore the box has gained some velocity due to the acceleration due to g and we can calculate it using 1/2mv²

Answer:

c

Explanation:

light refraction is a right angle

Answer: [tex]92.18\ m/s[/tex], east

Explanation:

Given

Ship is traveling at a speed of [tex]v=93\ m/s[/tex]

Direction of ship is [tex]25^{\circ}[/tex] North of east

If we break velocity vector in x and y axes then, the horizontal component is given by

[tex]\Rightarrow v_x=93\cos 25^{\circ}\\\Rightarrow v_x=92.18\ m/s[/tex]

The direction of horizontal component is towards east with magnitude of [tex]92.18\ m/s[/tex]

Answer:

This is based upon the fact that meteorites are generally believed to have originated as solid debris from Larger bodies like meteoroid or asteroids

Explanation:

Iron meteorites are interpreted as deriving from the cooled metallic core of a larger asteroid , because meteorites are generally believed to have originated as solid debris from Larger bodies like meteoroid or asteroids that are located outside the planet but found their way into our planet .

Answer:

Applications of Gravitational Force:

Answer:

The correct solution is:

(a) 1680 W

(b) 504 W

(c) 1.240

Explanation:

The given values are:

Voltage,

V = 120 V

Current of blow dryer,

I₁ = 14 A

Current of vacuum cleaner,

I₂ = 4.2 A

Time,

t₁ = 16 min

t₂ = 43 min

As we know,

⇒ [tex]Power (P) = VI[/tex]

(a)

For blow dryer:

⇒ [tex]P_1=V\times I_1[/tex]

        [tex]=120\times 14[/tex]

        [tex]=1680 \ W[/tex]

(b)

For Vacuum cleaner:

⇒ [tex]P_2=V\times I_2[/tex]

        [tex]=120\times 4.2[/tex]

        [tex]=504 \ W[/tex]

(c)

The ratio will be:

= [tex]\frac{Blow \ dryer \ energy}{Vacuum \ cleaner \ energy}[/tex]

= [tex]\frac{P_1\times t_1}{P_1\times t_2}[/tex]

= [tex]\frac{1680\times 16}{504\times 43}[/tex]

= [tex]\frac{26880}{21672}[/tex]

= [tex]1.240[/tex]

Answer:

Without the ability to measure, it would be difficult for scientists to conduct experiments or form theories. Not only is measurement important in science and the chemical industry, it is also essential in farming, engineering, construction, manufacturing, commerce, and numerous other occupations and activities.

Explanation:

Answer:

Rmains constant

Explanation:

The equation of the trajectory of a projectile motion is presented as follows;

[tex]Y = x \cdot tan \theta -\dfrac{g \cdot x^2}{2 \cdot u^2 \cdot cos^2 \theta}[/tex]

The vertical componet of the prjectile motion is

y = (u·sinθ)·t - g·t²/2

Where;

θ = The angle with which the projectile is launched

x = The horizontal distance

u = The initial velocity of the projectile

g = The acceleration due to gravity = Constant

t = The time of motion

The acceleration acting on the projectile is the 'g' which is the constant acceleration due to gravity

Therefore, for general projectile motion with no air resistance, the vertical component of the projectile acceleration remains constant

Answer:

1 kg

Explanation:

Applying,

Hook's law,

F = ke................. Equation 1

Where F = force, k = force constant of the spring, e = extension.

But from the question,

The weight of the bottle is the force acting on the spring scale

therefore,

mg = ke............ Equation 2

Where m = mass of the bottle, g = acceleration due to gravity.

make k the subject of the equation

k = mg/e............ Equation 3

Given: m = 0.5 kg, e = 1 cm = 0.01 m

Constant: g = 9.8 m/s²

k = (0.5×9.8)/0.01

k = 490 N/m

If the mass of the second bottle is weighed,

given: e = 2 cm = 0.02 m

subtitute into equation 1

m×9.8 = 490×0.02

9.8m = 9.8

m = 9.8/9.8

m = 1 kg.

Hence the mass of the second bottle is 1 kg

Explanation:

When the wire is connected to a battery, the compass needle moves and changes its position. This happens because the needle magnetizes the copper wire, thus,  creating a force.

While the current in the wire produces a magnetic field and exerts a force on the needle. The insulation on the wire becomes energized and exerts a force on the needle. Hence, the compass needle moves and changes its position.

Answer:

539.55 N for both

Explanation:

F=ma

Mass is given at 55kg

And when finding gravitational force gravity's constant is an acceleration of 9.81m/s

F=(55)(9.81)

F= 539.55 N (for both)

Normal force cancels out gravitational force that's why we don't fall throught the floor.

We push down on the floor due to gravitational force but normal force keeps us upright pushing an equal amount back.

Answer:

v1= 12.5miles, t= -7.25m, a= 0

v= 1/2at^2

v= 1/2×

Answer:

Explanation:

The equation for acceleration is

[tex]a=\frac{v_f-v_0}{t}[/tex]. We have the initial velocity since we are told that the car started from rest. What we don't have is the final velocity. But we can find it because we were told that the car undergoes uniform acceleration, so the equation

d = rt will give us that final velocity.

120 = r(6.32) so the velocity or rate of the car is

r = 19 m/s. Plug that in to find the acceleration of the car:

[tex]a=\frac{19-0}{6.32}[/tex] so

a = 3.0 m/s/s