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Which of the following statements are true of an object moving in a circle at a constant speed? Include all that apply.a) Because the speed is constant, the acceleration is zero.b) If the net force acting upon the object is suddenly reduced to zero, then the object would suddenly depart from its circular path and travel tangent to the circle.c)The object experiences a force which has a component directed parallel to the direction of motion.d)Inertia causes objects to move in a circle.e)The acceleration and the net force vector are directed perpendicular to each other.f)There can be a force pushing outwards on the object as long as the net force in inwards.g)The acceleration of the object is directed tangent to the circle.

User GoldenGonaz
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ANSWER:

b) and f)

Explanation:

To determine the answer we analyze option by option as follows:

a) Because the speed is constant, the acceleration is zero:

Acceleration happens when there is a change in velocity. Since the direction of the velocity vector is changing, there is an acceleration, an inward acceleration.

Therefore this is false.

b) If the net force acting upon the object is suddenly reduced to zero, then the object would suddenly depart from its circular path and travel tangent to the circle.

We have that if the net force is 0 N, then the moving object will maintain its state of motion and at the instant, the net force becomes 0 N, the object is moving tangent to the circle.

So this option is true

c) The object experiences a force which has a component directed parallel to the direction of motion.

We have that if the movement is circular at a constant speed, the net force is perpendicular to the direction of movement and this means that there is no component parallel or antiparallel to the direction of movement.

Therefore, this option is false.

d) Inertia causes objects to move in a circle.

The centripetal force that causes circular motion.

So this option is false

e) The acceleration and the net force vector are directed perpendicular to each other.

Acceleration and net force are always directed in the same direction. But in this case, they are directed inwards; this happens to be perpendicular to the tangential velocity vector.

So this option is false

f) There can be a force pushing outwards on the object as long as the net force in inwards.

An object moving in a circle must have a net internal force. And it may be the case where individual external forces are overcome by an individual internal force.

That is to say that this option is true

g) The acceleration of the object is directed tangent to the circle. We have that the acceleration is directed inwards; only the velocity is directed tangent to the circle.

So this option is false.

This means that the only true options are b) and f)

User Arne Brasseur
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