Show all of your work for the following questions and circle your answer! (4 points) The driver of a 9800 N car is cruising along at 35 m/s and removes her foot from the gas pedal
for 7s when her speed is then 30 m/s. What force of friction caused her car to slow down during that
time. Draw and completely label a free-body diagram for full credit.
(4 points) A 300 N wagon (with a child in it) are being pulled from rest. They are pulled with 40 N of force
against 25 N of friction. After being pulled for 5 s, how fast is the wagon & child combo now moving?
Draw and completely label a free-body diagram for full credit.

In a thunderstorm, charge builds up on the water droplets or ice crystals in a cloud. thus, the charge can be considered to be distributed uniformly throughout the cloud. for the purposes of this problem, take the cloud to be a sphere of diameter 1.00 kilometer. the point of this problem is to estimate the maximum amount of charge that this cloud can contain, assuming that the charge builds up until the electric field at the surface of the cloud reaches the value at which the surrounding air breaks down. this breakdown means that the air becomes highly ionized, enabling it to conduct the charge from the cloud to the ground or another nearby cloud. the ionized air will then emit light due to the recombination of the electrons and atoms to form excited molecules that radiate light. in addition, the large current will heat up the air, resulting in its rapid expansion. these two phenomena account for the appearance of lightning and the sound of thunder. take the breakdown electric field of air to be eb=3.00ă—106n/c. part a estimate the total charge q on the cloud when the breakdown of the surrounding air is reached. express your answer numerically, to three significant figures, using ďµ0=8.85ă—10â’12c2/(nâ‹…m2) .

Select the three ways that the parallel-plate capacitor differs from a car battery.

Emagnitude of the electrical force acting between a +2.4 ×  10–8  c charge and a +1.8 ×  10–6  c charge that are separated by 0.008 m is    n, rounded to the tenths place.