Questions from College Physics

Q: In a circus performance, a monkey is strapped to a sled

In a circus performance, a monkey is strapped to a sled and both are given an initial speed of 4.0 m/s up a 20.0° inclined track. The combined mass of monkey and sled is 20. kg, and the coefficient of...

Q: An 80.0 - kg skydiver jumps out of a balloon

An 80.0 - kg skydiver jumps out of a balloon at an altitude of 1.00 x 103 m and opens the parachute at an altitude of 200.0 m. (a) Assuming that the total retarding force on the diver is constant at 5...

Q: A skier of mass 70.0 kg is pulled up a

A skier of mass 70.0 kg is pulled up a slope by a motordriven cable. (a) How much work is required to pull him 60.0 m up a 30.0° slope (assumed frictionless) at a constant speed of 2.00 m/s? (b) What...

Q: What average mechanical power must a 70.0 - kg mountain

What average mechanical power must a 70.0 - kg mountain climber generate to climb to the summit of a hill of height 325 m in 45.0 min? Note: Due to inefficiencies in converting chemical energy to mech...

Q: While running, a person dissipates about 0.60 J of

While running, a person dissipates about 0.60 J of mechanical energy per step per kilogram of body mass. If a 60. - kg person develops a power of 70. W during a race, how fast is the person running? (...

Q: Two masses m1 and m2, with m1 < m2, have

Two masses m1 and m2, with m1 < m2, have equal kinetic energy. How do the magnitudes of their momenta compare? (a) Not enough information is given. (b) p1 < p2 (c) p1 = p2 (d) p1 > p2.

Q: The electric motor of a model train accelerates the train from rest

The electric motor of a model train accelerates the train from rest to 0.620 m/s in 21.0 ms. The total mass of the train is 875 g. Find the average power delivered to the train during its acceleration...

Q: The electric motor of a model train accelerates the train from rest

The electric motor of a model train accelerates the train from rest to 0.620 m/s in 21.0 ms. The total mass of the train is 875 g. Find the average power delivered to the train during its acceleration...

Q: Under normal conditions the human heart converts about 13.0 J

Under normal conditions the human heart converts about 13.0 J of chemical energy per second into 1.30 W of mechanical power as it pumps blood throughout the body. (a) Determine the number of Calories...

Q: A certain rain cloud at an altitude of 1.75 km

A certain rain cloud at an altitude of 1.75 km contains 3.20 x 107 kg of water vapor. How long would it take for a 2.70 - kW pump to raise the same amount of water from Earth’s surface to the cloud’s...