Force is the change in momentum over a specific time. The change of momentum is therefore the force multiplied by the time that the force acts, so 3000x4.0=12000 N s=12000 kg m/s
Answer: Speed = 4 m/s
Explanation:
The parameters given are
Mass M = 60 kg
Height h = 0.8 m
Acceleration due to gravity g= 10 m/s2
Before the man jumps, he will be experiencing potential energy at the top of the table.
P.E = mgh
Substitute all the parameters into the formula
P.E = 60 × 9.8 × 0.8
P.E = 470.4 J
As he jumped from the table and hit the ground, the whole P.E will be converted to kinetic energy according to conservative of energy.
When hitting the ground,
K.E = P.E
Where K.E = 1/2mv^2
Substitute m and 470.4 into the formula
470.4 = 1/2 × 60 × V^2
V^2 = 470.4/30
V^2 = 15.68
V = square root (15.68)
V = 3.959 m/s
Therefore, the speed of the man when hitting the ground is approximately 4 m/s
Answer:
I₁ > I₃ > I₂
Explanation:
Taking the pic shown, we have
m₁ = 10m₀
m₂ = 2m₀
m₃ = m₀
r₁ = r₀
r₂ = 2r₀
r₃ = 3r₀
We apply the formula
I = mr²
then
I₁ = m₁r₁² = (10m₀)(r₀)² = 10m₀r₀²
I₂ = m₂r₂² = (2m₀)(2r₀)² = 8m₀r₀²
I₃ = m₃r₃² = (m₀)(3r₀)² = 9m₀r₀²
finally we have
I₁ > I₃ > I₂
According to Ohm's Law, the resistance, current and voltage are related as:
V = IR
⇒
R = V/I
V is given to be 12 Volts.
I is given to be 0.5 Ampere
So, resistance will be:
R = 12/0.5 = 24 ohms
