Other Physics Answers

Neil Armstrong was the first man to walk on the moon. On July 20, 1969, his famous statement, "That's one small step for man, one giant leap for mankind." was received at 10:56 p.m. ( EDT) on Earth. (a) How long did it take his voice to reach Earth via radio waves? (b) At what time (in EDT) did he utter this statement at the surface of the moon. The distance between the Earth and the moon is 3.85 x 10^12 m.

The temperature of a 0.700 kg cube of ice is decreased

to -150 C. Then energy is gradually transferred to the cube as

heat while it is otherwise thermally

isolated from its environment. The

total transfer is 0.6993 MJ. Assume

the value of c for ice given

is valid for temperatures from

-150 C to 0 C. What is the final

temperature of the water?

The electric field has a magnitude of 3.0 N/C at a distance of 60 cm from a point charge..What is the charge?

1. Will a 0.30 m × 0.30 m × 0.30 m empty copper (ρ_Cu = 8890 kg/m³) box float in water? The total mass of copper is 3.2 kg.

A rectangular surface of length 3.25 cm and width 5.25 cm lies on the x-z plane at y=0. What is the flux through this surface due to a uniform magnetic field of 0.65 T directed 60° from the +x-axis?

A closely wound 0.20m × .20 m square coil of 100 turns is exposed to an external magnetic field of 0.74 T that is perpendicular to the plane of the coil. The coil is then rotated for 10 s until it makes 60 degrees with the magnetic field. Find the average induced electromotive force during the 10 s interval.

Computation:

A 50000 g object accelerates with a force of 500 newtons. Find the acceleration of the object.

A satellite is projected near the surface of Earth so that it has a certain speed that can orbit the Earth. Calculate the speed of the satellite and the time for 1 complete rotation around the Earth. (Given, ME = 6 x 1024 kg, RE = 6.38 x 106 m, G = 6.67 x 10-11 Nm2kg-2)

A fisherman on a stationary boat jumps off onto a jetty with a velocity of 1.5 ms-1, causing the boat to move backwards.

(i) If the mass of the fisherman and the boat are 65 kg and 450 kg respectively, determine the velocity of the boat. (ii) If the fisherman’s feet are in contact with the jetty for 10 ms, determine the magnitude of the average force exerted on his feet.

A 65.0 kg astronaut is doing a repair in space on the orbiting space station. The astronaut throws a what 2.50 kg toolbox away from him at 3.50 m/s to the space station. (a) With what speed and in direction will he begin to move? (b) How much kinetic energy does the astronaut create by this maneuver?