
<u>Explanation:</u>
Velocity of B₁ = 4.3m/s
Velocity of B₂ = -4.3m/s
For perfectly elastic collision:, momentum is conserved

where,
m₁ = mass of Ball 1
m₂ = mass of Ball 2
v₁ = initial velocity of Ball 1
v₂ = initial velocity of ball 2
v'₁ = final velocity of ball 1
v'₂ = final velocity of ball 2
The final velocity of the balls after head on elastic collision would be

Substituting the velocities in the equation

If the masses of the ball is known then substitute the value in the above equation to get the final velocity of the ball.
Answer:
Mechanical resonance is the tendency of a mechanical system to respond at greater amplitude when the frequency of its oscillations matches the system's natural frequency of vibration (its resonance frequency.
Explanation:
Answer:
the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.
K = E - Ф
Explanation:
The photoelectric effect is the emission of electrons from the surface of a metal.
This was correctly explained by Einstein, in his explanation the energy of the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.
E = hf
E = K + Ф
K = E - Ф
The energy of the photons is given by the Planck relation E = hf and according to Einstein the number of joints must be added
E = n hf
Therefore, depending on the value of this energy, the emitted electrons can have energy from zero onwards.
Answer: 1.95s
Explanation:
Given
ma = 290 cos 34.9 - fk
fk = 290 cos 34.9 - ma
fn = mg + 400 sin Φ
fn = 290 + 400 sin 34.9
fn = 290 + 228.9
fn = 518.9
fk = fn * uk
uk = 0.57
290 cos 34.9 - ma = 518.9 * 0.57
290 cos 34.9 - ma = 295.8
290 cos 34.9 - 295.8 = ma
ma = -58
m = 290/10 = 29
a = 58/29
a = 2
Using equation of motion
S = ut + .5at²
3.8 = 0 + .5*2*t²
3.8 = t²
t = 1.95s