An athlete jumping vertically on a trampoline leaves the surface with a velocity of 8.5 m/s upward. What maximum height does she reach? (a) 13 m (b) 2.3 m (c) 3.7 m (d) 0.27 m (e) The answer cant be determined because the mass of the athlete isnt given.

An electric scooter has a battery capable of supplying 120 Wh of energy. If friction forces and other losses account for 60.0% of the energy usage, what altitude change can a rider achieve when driving in hilly ter-rain if the rider and scooter have a combined weight of 890 N?

As a young man, Tarzan climbed up a vine to reach his tree house. As he got older, he decided to build and use a staircase instead. Since the work of the gravitational force mg is path Independent, what did the King of the Apes gain in using stairs?

Consider a particle on which a force acts that depends on the position of the particle. This force is given by . Find the work done by this force when the particle moves from the origin to a point 5 meters to the right on the x-axis.

Assume that the force of a bow on an arrow behaves like the spring force. In aiming the arrow, an archer pulls the bow back 50 cm and holds it in position with a force of 150 N. If the mass of the arrow is 50 g and the “spring” is massless, what is the speed of the arrow immediately after it leaves the bow?

A catapult launches a large stone from ground level at a speed of 45.0 m/s at an angle of 55.0 with the horizontal. The stone returns to ground level shortly thereafter, (a) How long is it in the air? (b) What maximum height does the stone reach? (Neglect, air friction.) (See Section 3.4.)

A 537-kg trailer is hitched to a truck. Find the work done by the truck on the trailer in each of the following cases. Assume rolling friction is negligible. a. The trailer is pulled at constant speed along a level road for 2.30 km. b. The trailer is accelerated from rest to a speed of 88.8 km/h. c. The trailer is pulled at constant speed along a road inclined at 12.5 for 2.30 km.

Check Your Understanding You probably recall that, neglecting air resistance, if you throw a projectile straight up, the time ii takes to reach its maximum height equals the time it takes to fall from the maximum height back to the starting height. Suppose you cannot neglect air resistance, as in Example 8.8. Is the time the projectile takes to go up (a) greater than, (b) less than, or (c) equal to the time It takes to come back down? Explain.

A 60.0 kg skier with an initial speed of 12.5 m/s coasts up a 2.50 m high rise as shown in the figure. Find her final speed right at the top, in meters per second, given that the coefficient of friction between her skis and the snow is 0.31.