Centripetal Force

Q.

What is the meaning of "intrinsic"?

Q.

Why is centrifugal force called a fictional force?

Q.

If the centripetal force to keep the ball in a horizontal circular loop is $10N$, it achieves an angular velocity of $0.25rad/s$ with a radius $10m$, then calculate its required mass.

1. $1.6kg$

2. $16kg$

3. $16g$

4. $0.16kg$

Q.

A 2 kg ball on a string is rotated about a circle of radius 10 m. The maximum tension allowed in the string is 50 N. What is the maximum speed of the ball?

1. 21.2 m/s

2. 15.8 m/s

3. 40.8 m/s

4. 11.11 m/s

Q. Assertion : Centripetal and centrifugal forces cancel each other.
Reason : Centrifugal force is a reaction of centripetal force.

1. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion
2. If both Assertion and Reason are true but the Reason is not the correct explanation of the Assertion
3. If Assertion is true statement but Reason is false
4. If both Assertion and Reason are false statements

Q. Define centripetal force. Write the expression for it.

Q. During the course of a turn, an automobile doubles its speed. How much additional frictional force must the tires provide if the car safely makes around the curve?

1. An increase in velocity by a factor of two must be accompanied by an increase in centripetal force by a factor of four.
2. An increase in velocity by a factor of two must be accompanied by an increase in centripetal force by a factor of half
3. An increase in velocity by a factor of two must be accompanied by an increase in centripetal force by a factor of eight.
4. An increase in velocity by a factor of two must be accompanied by an decrease in centripetal force by a factor of half.

Q.

When a ball is whirling is a circle and the string supporting it suddenly break up, then the

1. ball stops

2. ball flies away tangentially

3. ball falls towards the center

4. None of the above

Q. Question 6
A stone of 1 kg is thrown with a velocity of $20m{s}^{-1}$ across the frozen surface of a lake and comes to rest after travelling a distance of 50 m. What is the force of friction between the stone and the ice?

Q.

A $200kg$ motorcycle is driven around a $14m$ radius horizontal circular loop at a constant speed of $15m/s$. Calculate the required centripetal force on the motorcycle.

1. $F=321N$

2. $F=3214.3N$

3. $F=1214.3N$

4. $F=3614.3N$

Q.

Two bodies A and B in space are attracting each other due to gravitational force. The force of attraction on B due to A is ___ to the force of attraction due to A on B.

Q. Write the difference between revolutionary motion and rotatory motion. Give one example for each.

Q.

A stone tied to a string when whirled in a vertical circular loop___

1. the weight of a stone provides the centripetal force

2. angular acceleration provides required centripetal force

3. instantaneous speed provides centripetal force

4. tension in the string provides required centripetal force

Q. A racecar, moving at a constant speed of $60m/s$ in a circular track of radius $100m$. Then, the centripetal acceleration is given by ___ $m/s^2$.

1. 16.6
2. 36
3. 3.6
4. 1.66

Q.

During the course of a turn, an automobile doubles its speed. What change will we observe in centripetal force?

1. Gets halved.

2. Becomes eight times.

3. Becomes four times.

4. Becomes twice.

Q.

Name the branch of Science which explains force and displacement.

Q.

The figure shows a smoothly curved track terminating in a smooth horizontal part. A spring of spring constant 400 N/m is attached at one end to a wedge fixed rigidly with the horizontal part. A 40 g mass is released from rest at a height of 4.9 m on the curved track. Find the maximum compression of the spring. (g = 9.8 m/$s^2$)

1. 4.6 m

2. 9.8 m

3. 4.9 m

4. None of these

Q.

A stone of mass 5 kg is tied to a string of length 4 m. If the stone is swirled around by a boy with a linear speed of 20 m/s, what is the centripetal force acting on the stone?

1. 50 N

2. 250 N

3. 25 N

4. 125 N

Q.

A piece of stone tied at the end of a thread is whirled in a horizontal circle.

The force which provides the centripetal force is

1. Tension in the thread

2. Gravitational force

3. Frictional force

4. Electromagnetic force

Q.

Explain elastic waves using conservation of momentum.

Q. 1. Let us assume that you have the power of creating the universe as it is. What is the minimum things u would need to do that ?

2. When you are pushing a box on the table, are u really touching the box ? Think in terms of your atoms interacting with the box's atoms ?

3. A ball when slide on a horizontal surface eventually comes to a stop , even though seemingly no force is acting on it . Doesn't this contradict Gallelio's statement ?

Q. With reference to the direction of action, how does a centripetal force differ from a centrifugal force?

1. They act in opposite directions.
2. They act as action reaction pair.
3. They act in same direction.
4. Both A & B

Q.

State the difference between mass and weight of a body.

Q.

A boy is rotating a stone of mass $500g$ by using a string of length $50cm$ in a circular motion, with a speed $10cm/s$. What will be the work done by the force applied by the boy?

1. $0.01\mathrm{\pi }\mathrm{J}$

2. $\mathrm{\pi }\mathrm{J}$

3. $10\mathrm{\pi }\mathrm{J}$

4. zero

Q.

A compressed spring releases a toy of mass 50g attached to it at 200cm/s. Calculate the elastic PE of the compressed string.

1. 0.3 J

2. 0.4 J

3. 0.5 J

4. 0.2 J

5. 0.1 J

Q. A satellite is orbiting round the earth. The centripetal force acting on the satellite is $F$. The force of the satellite on the earth is also $F$. The net force on the satellite is :

1. $F$
2. $zero$
3. $2F$
4. $\frac{F}{2}$

Q. Centripetal force is

1. A force that makes particle to spin about its axis
2. A force that makes particle to vibrate about their mean position
3. A force that makes its speed to be constant
4. A centre seeking force

Q. A stone tied to a string is rotated in a circle. If the string is cut, the stone flies away from the circle because

1. A centripetal force acts on the stone
2. A centrifugal force acts on the stone
3. of its inertia
4. Reaction of the centripetal force

Q. A particles of mass m move with constant velocity v on circular path of radius r find magnitude of average force on it in half revolution

Q. Figure shows the circular motion of a particle. The radius of the circle, the period, sense of revolution and the initial position are indicated on the figure. The simple harmonic motion of the $x$ - projection of the radius vector of the rotating particle P is:

1. $x\left(t\right)=Bsin\left[\frac{2\pi }{30}t\right]$
2. $x\left(t\right)=Bcos\left[\frac{2\pi }{15}t\right]$
3. $x\left(t\right)=Bcos[\frac{\pi }{15}t+\frac{\pi }{2}]$
4. $x\left(t\right)=Bsin[\frac{\pi }{15}t+\frac{\pi }{2}]$