Answer:
Explanation:
Based on the wave model of light, physicists predicted that increasing light amplitude would increase the kinetic energy of emitted photoelectrons, while increasing the frequency would increase measured current.
Contrary to the predictions, experiments showed that increasing the light frequency increased the kinetic energy of the photoelectrons, and increasing the light amplitude increased the current.
Based on these findings, Einstein proposed that light behaved like a stream of particles called photons with an energy of \text{E}=h\nuE=hνstart text, E, end text, equals, h, \nu.
The work function, \PhiΦ\Phi, is the minimum amount of energy required to induce photoemission of electrons from a metal surface, and the value of \PhiΦ\Phi depends on the metal.
The energy of the incident photon must be equal to the sum of the metal's work function and the photoelectron kinetic energy:
need speed of sound on lhs
We have the equation of motion 
, where v i the final velocity, u is the initial velocity, a is the acceleration and s is the displacement
Here final velocity, v = 40m/s
Initial velocity, u = 0 m/s
Displacement s = 2 m
Substituting 
So the baseball pitcher accelerates at 400m/
to release a ball at 40 m/s.
If the object is in equilibrium that means that the sum of the forces on it is zero and the net force is zero. If none of the forces changes then the object continues in constant uniform motion. That means constant speed in a straight line.
or one hailstone we have;
Force = Mass X acceleration = 0.005kg x 9.8.} This is when the hailstone is not inclined at an angle.
When the hailstone is inclined at an angle of 45, then the component of force along the glass window will be F =0.005kg x 9.8 x sin45= 0.005kg x 9.8 x 0.707= 0.0346N.
Therefore, total force for the 500 hailstones would be 500x0.0346N=17.32N
This force is acting on an area equal to 0.600m2
Pressure = Force per unit area = 17.32N/0.600m2 = 28.9Pa
