Summarize Newton’s First Law
1 answer:
You might be interested in
Answer:
(A) Torque required is 21.205 N-m
(b) Wok done will be equal to 1199.1286 j
Explanation:
We have given moment of inertia
Wheel deaccelerate from 135 rpm to 0 rpm
135 rpm =
Time t = 8 sec
So angular speed and
Angular acceleration is given by
Torque is given by torque
Work done to accelerate the vehicle is
Answer:
4.15 m/s
Explanation:
As the total energy must be conserved (neglecting air resistance) the change in gravitational potential energy, must be equal to the change in kinetic energy:
ΔE = ΔK + ΔU =0
If we take as a zero reference level for the gravitational potential energy, the height of the swing seat above the ground, (which is equal to 0.21 m), we can find the initial gravitational energy, considering the height of the point where the seat is released, regarding this point:
h₀ = 1.09 m -0.21 m = 0.88 m
⇒ U₀ = m*g*h₀ = 400 N*0.88 m = 352 J
As Uf = 0, ΔU = Uf -U₀ = -352 J
As the swing starts from rest, K₀=0, so we can say:
ΔK = Kf = (1)
As ΔK = -ΔU ⇒ ΔK = 352 J (2)
From (1) and (2) we can solve for vf, as follows:
So, when the swing passes through its lowest position, Betty moves at 4.15 m/s.