A 60-kg teenager is standing on a skateboard. What force does the skateboard exert on the

teenager?

Name 3 objects that have gravitational potential energy?

How does our sun differ from most other main sequence stars?

A 90.0 kg man climbs hand over hand up a rope to a height of 9.47 m. How much potential energy does he have when he reaches the top?

The difference between newtons first law of motion and newtons third law of motion

The type of coal that has the highest carbon content is

A 100 N box is placed on an inclined plane that makes a 30° angle with the horizontal. Calculate the component of gravitational force that acts down the inclined plane. A. 25 N B. 50 N C. 87 N D. 100 N

Approximately how many kelvins are equal to 60 c? a. 289k b. 323k c. 333k d. 413k

What are two ways to change velocity?

What is the main optical element of a refracting telescope?

Two water manometers are connected to a tank of air. One leg of the manometer is open to 100kPa pressure (absolute) while the other leg is subjected to 90kPa. Find the difference in deflection between both manometers, Delta h_a - Delta h_b.