Classical Mechanics Answers

Does a planet that has a greater mass than Earth necessarily have a greater acceleration due to gravity near its surface? (Saturn, for example, has about a hundred times the mass of Earth.)
1 : Yes
2 : No
3 : More information is needed to say

The length of a year on any planet is defined as the time interval the planet takes to make one revolution around the Sun. What is the length of a year on a planet whose orbital radius is four times Earth’s orbital radius?
1 : 1 Earth year
2 : 2 Earth years
3 : 4 Earth years
4 : 8 Earth years
5 : 0.5 Earth years
6 : 0.25 Earth years
7 : 0.125 Earth years

A baseball is located at the surface of the earth. Which statements about it are correct? (There may be more than one correct choice.)
1 : The earth exerts a much greater gravitational force on the ball than the ball exerts on the earth.
2 : The ball exerts a greater gravitational force on the earth than the earth exerts on the ball.
3 : The gravitational force on the ball due to the earth is exactly the same as the gravitational force on the earth due to the ball.
4 : The gravitational force on the ball is independent of the mass of the ball.
5 : The gravitational force on the ball is independent of the mass of the earth

If you change the sequence of the two vectors in the vector(cross) product, what will happen?
1 : The magnitude of the resultant vector will change and the direction will be opposite
2 : The magnitude of the resultant vector will change and the direction will be same
3 : The magnitude of the resultant vector will be same and the direction will be opposite
4 : The magnitude of the resultant vector will be same and the direction will be same

if the round object is a ring, using I=mR^2, what is the fraction of rotational kinetic energy over the total kinetic energy?
1 : 1/4
2 : 1/3
3 : 1/2
4 : 2/3
5 : 1

, if the round object is not a disk but a ring I=mR^2, the acceleration will be?
1 : same
2 : smaller
3 : larger
4 : depend on the inertia of the object
5 : depend on the angle of the slope

Which of the following is an accurate statement?
1 : The magnitude of a vector can be zero even though one of its components is not zero.
2 : It is possible to add a scalar quantity to a vector.
3 : Even though two vectors have unequal magnitudes, it is possible that their vector sum is zero.
4 : Rotating a vector about an axis passing through the tip of the vector does not change the vector.
5 : The magnitude of a vector is independent of the coordinate system used

How efficient is a slide when the following occurs. The slide is 30m high and a little boy pushes off and slides down the slide with an initial velocity of 5.0 km/h and reaches the bottom while travelling 20 km/h.

When driving between two locations, the first half of the route is speed limited to 50 km / h and the second half is limited to 70 km / h. Olle puts the cruise control in his car at 60 km / h and keeps this speed throughout the journey. He believes this will mean that it will take just as long to drive between the resorts, as when he is law-abiding and follows the speed limits. To his surprise, he finds that it differs 2.0 minutes in time.
How far is it between the resorts?

Two disks with the same inertia 1kg are rotating along the same axis.
• Disk A has radius 2m and disk B has radius 4m.
• Disk A is rotating with 2rad/s, ω direction up
• Disk B is rotating with 1rad/s, ω direction down
• Now the two disks are jointed together, calculate
the final angular momentum of the combined disks