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Which of the following deductions is/are true from Newton's first law of motion?

1) The velocity of a body, in the absence of a resultant force, is always zero.

2) A body is always reluctant to change its state of motion.

3) A resultant force is NOT necessary to produce a change in velocity.

If 2 and 3 are correct.

If 3 only is correct.

If 1 and 2 are correct.

If 1 only is correct.

Which of the following is correct?

It is possible for the speed of a body to change without the body accelerating.

A change in the velocity of an object implies a change in its speed.

A body can be accelerating in a direction opposite to that of its velocity.

It is NOT possible for a body to be at rest and yet have an acceleration.

A car travelling at 60 km per hour passes a truck going at 30 km per hour that has four times the mass of the car.

Which of the following is true?

1) The car and the truck have the same momentum and the same kinetic energy.

2) The truck has greater kinetic energy than the car.

3) The car has the same kinetic energy and half as much momentum as the truck.

If 1 only is correct.

If 2 and 3 are correct.

If 1 and 2 are correct.

If 3 only is correct.

A hollow plastic ball and a solid metal ball all of the same external radius are both released from rest in a vacuum chamber.

After falling for one minute, they will have the same:

Speed.

Inertia.

Change in momentum.

Kinetic energy.

The air resistance experienced by a moving car can be reduced by:

Driving at steady speed.

Driving on a tarred road.

Reducing the speed.

Increasing the speed.