Suppose that the gravitational acceleration on a certain planet is only 2.4 m/s². A space explorer standing on this planet throws a ball straight upward with an initial velocity of 25 m/s.

(a) What is the velocity of the ball 4 seconds after it is thrown?
m/s
(b) How much time elapses before the ball reaches the high point in its flight?
s

The diagram below shows a wastebasket placed behind a chair. Three different directions are indicated for the velocity of a ball thrown by the kneeling woman.

Which of the three directions, A, B, or C, is likely to result in the ball landing in the basket? (Select all that apply.)

A ball on the end of a string is whirled with constant speed in a counterclockwise horizontal circle. At point A in the circle, the string breaks.

Which of the curves sketched in the above diagram most accurately represents the path that the ball will take after the string breaks (as seen from above)?

In the circuit shown below, the R₁ = 3 resistance is the internal resistance of the battery and can be considered to be in series, as shown, with the battery and the R₂ = 10 load.

(a) What is the current flowing through the 10 resistor?
A
(b) What is the voltage difference across the 10 resistor?
V

A wave on a rope is shown in the diagram below with L = 5 m.

(a) What is the wavelength of this wave?
m
(b) If the frequency of the wave is 3.0 Hz, what is the wave speed?
m/s