Answer:
m1 = the mass of the blue sphere = 5.8 kg
m2 = the mass of the red sphere = 2.5 kg
v1 = initial velocity of the blue sphere before the collision = 4.1 m/s
v2 = initial velocity of the red sphere before the collision = 0 m/s
v'1 = final velocity of the blue sphere after the collision = 1.3 m/s
v'2 = final velocity of the red sphere after the collision = ?
using conservation of momentum
m1v1 + m2v2 = m1v'1 + m2v'2
(5.8) (4.1) + (2.5) (0) = (5.8) (1.3) + (2.5) (v'2)
23.78 = 7.54 + (2.5) (v'2)
-7.54 -7.54
16.24 = (2.5) v'2
--------- -----------
2.5 2.5
v'2 = 6.5
Explanation:
The watch hand covers an angular displacement of 2π radians in 60 seconds.
ω = 2π/60
ω = 0.1 rad/s
v = ωr
v = 0.1 x 0.08
v = 8 x 10⁻³ m/s
Answer:
The frequency of an ocean wave is 15 Hz.
Explanation:
We are given with, the speed of an ocean wave is 45 m/s. Its wavelength is 3 m
It is required to find the frequency of an ocean wave.
The speed of a wave is given in terms of frequency and wavelength as :
,
f = frequency of ocean wave

So, the frequency of an ocean wave is 15 Hz.
Answer:
reviewing the opinion of the two students we see that neither is right, since when the kinetic energy increases the potential energy decreases by the same value
Explanation:
For this exercise we must use the law of conservation of energy.
Starting point. Resting electron
Em₀ = U = eV
the potential difference and the electric field are related
V = - E d
Final point. When leaving the electric field
= K = ½ m v²
Em₀ = Em_{f}
e E d = ½ m v²
From this expression we see that when an electron moves from the initial point to the final point, the potential energy must decrease, for the total energy to be constant.
When reviewing the opinion of the two students we see that neither is right, since when the kinetic energy increases the potential energy decreases by the same value