A 1.13 kg skateboard is coasting along the pavement at a speed of 4.28 m/s when a 0.93 kg cat drops from a tree vertically downward onto the skateboard. What is the speed of the
skateboard-cat combination?

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) .

Which safety measures should you follow during a thunderstorm? check all that apply. (a) avoid touching anything that conducts electricity. (b) avoid touching a person who has been struck by lightning. (c) go outside. (d) keep your computer turned off. (e) stay out of water. (f) stay inside.

Avery long solenoid of inner radius 2.75 cm creates an oscillating magnetic field of the form = for this solenoid, =0.00425 t and =319 rad/s. (a)what is the maximum value of the induced electric field at a perpendicular distance 1.45 cm from the axis of the solenoid? (b) what is the maximum value of the inducted electric field at a point 5.85 cm perpendicular from the axis of the solenoid?