Physics chapter 6

The following statements refer to man-made, artificial satellites in orbit around Earth. Which is an accurate statement?

A satellite in a large diameter circular orbit will always have a longer period of revolution about the Earth than will a satellite in a smaller circular orbit

Two children are riding on a merry-go-round. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger centripetal acceleration?

Child A

Two children are riding on a merry-go-round. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger linear displacement?

Child A

Two children are riding on a merry-go-round. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger tangential speed?

Child A

The net force on an object in orbit is zero.

False

When a rigid body rotates about a fixed axis all the points in the body have the same angularacceleration.

False

When a rigid body rotates about a fixed axis all the points in the body have the same centripetal acceleration

False

When a rigid body rotates about a fixed axis all the points in the body have the same linear-displacement.

False

When a rigid body rotates about a fixed axis all the points in the body have the same tangential acceleration.

False

When a rigid body rotates about a fixed axis all the points in the body have the same tangential speed.

False

A spaceship is traveling to the moon. At what point is it beyond the pull of Earth's gravity?

It is never beyond the pull of Earth's gravity

Consider a small satellite moving in a circular orbit (radius r) about a spherical planet (mass M).The period does not depend upon

The satellite mass

Satellite A has twice the mass of satellite T, and rotates in the same orbit. Which of the following is true?

The speed of T is equal to the speed of A.

Marilyn (M) and her sister Sheila (S) are riding on a merry-go-round, as shown in Fig. 7-3(bird's-eye view). Which of the following is true?

They have different speeds, but the same angular velocity

Two children are riding on a merry-go-round. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger angular displacement?

They have the same non-zero angular displacement

Two children are riding on a merry-go-round. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger angular speed?

They have the same non-zero angular speed.

When a rigid body rotates about a fixed axis all the points in the body have the same angular displacement

True

When a rigid body rotates about a fixed axis all the points in the body have the same angular-speed

True

A race car, traveling at a constant speed of 50 m/s, drives around a circular track of radius 250m. What angular acceleration does it experience?

Zero

A car, driven around a circle with constant speed, must have

a centripetal acceleration

James is twirling a rock around a horizontal circle on the end of a string. Fig. 7-4 is a top view(motion is counterclockwise). If the speed is constant what is the acceleration at point A?

centripetal

A pilot executes a vertical dive. Just before the plane starts to come up from the bottom of the dive, the force on him is

more than g, and pointing up

Does the centripetal force acting on an object do work on the object?

no, because the force and the displacement of the object are perpendicular

A satellite encircles Mars at a distance above its surface equal to 3 times the radius of Mars. The acceleration of gravity at the satellite, as compared to the acceleration of gravity on the surface of Mars, is

one-sixteenth as much

If the Earth had four times its present mass, what would be its new period of revolution around the sun, compared to its present orbital period?

the same