A penny falls from a windowsill which is 25.0 m above the sidewalk. How much time does a passerby on the sidewalk below have to move out of the way before the penny hits the ground?

A 1.2x10^3 kilogram car is accelerated uniformly from 10. meters per second to 20 meters per second in 5.0 seconds. what is the magnitude of the net force acting on the car during this 5.0 second interval

What must modelo and theories do in order to remain valid?

A child holds up a silver spoon and is surprised to see her reflection there. Which interaction between light and matter explains this? A.

N 80-kg man is one fourth of the way up a 10-m ladder that is resting against a smooth, frictionless wall.

Starting at t = 0 s, a horizontal net force F⃗ = (0.285 N/s) ti^ + (-0.460 N/s2) t2j^ is applied to a box that has an initial momentum p⃗ = (-3.10 kg⋅m/s) i^ + (3.90 kg⋅m/s) j^. What is the momentum of the box at t = 1.

Two sinusoidal waves are moving through a medium in the positive x-direction, both having amplitudes of 7.00 cm, a wave number of k=3.00m-1, an angular frequency of ω=2.50s-1, and a period of 6.00 s, but one has a phase shift of an angle ϕ=π12rad.

For a vacation, you and your family fly east to west from Boston, Massachusetts, to Seattle, Washington. You notice that your flight back home to Boston is shorter than your flight to Seattle. Which phenomenon causes your flight home to be shorter?

You spy on an anchor on the bottom of a lake. What is the direction and amount of force the water exerts on it: a) zero b) up, equal to the weight of the anchor. c) up, less than the weight of the anchor d) down, equal to the weight of the anchor.

How are electromagnetic waves different from matter waves?

A dc generator is the same as a (n) a. electric motor. b. ac generator. c. armature. d. electric current.