A baseball player (hitter) hits the ball with her bat. The ball flies north at an angle a above ground and with an initial speed v towards a fielder whose job is to catch the ball before it hits the ground. The distance between the fielder and the hitter is D. At the moment when the bat hits the ball, the fielder starts running to the south towards the place where he believes the ball will fall. Assume the fielder runs with a constant speed all the time the ball is in the air. Assume the hand of the fielder catches the ball just before it hits the ground and that the ball is hit by the bat at ground level. How fast must the fielder run to be able to catch the ball?

Suppose that an electromagnetic wave which is linearly polarized along the x−axis is propagating in vacuum along the z−axis. the wave is incident on a conductor which is placed at z > 0 region of the space. the conductor has conductivity σ, magnetic permeability µ and electric permittivity ε. (a) find the characteristic time for the free charge density which dissipates at the conductor. (b) write the maxwell equations and derive the wave equation for a plane wave propagating in a conductor. (c) find the attenuation distance at which the incident amplitude reduces to e ^−1 of its initial value. (d) find the electric and magnetic fields inside the conductor. 8 (e) find the power loss per area of the incident electromagnetic wave at the surface of conductor.

The sound level near a noisy air conditioner is 70 db. if two such units operate side by side, the sound level near the, would bea. 70dbb. 73 dbc. 105 dbd 140 db

Which of the following statements accurately describes the sign of the work done on the box by the force of the push? a. positive b. negative c. zero