Answer:

Explanation:
Given data
Mass m=67.0 kg
Final Speed vf=8.00 m/s
Initial Speed vi=2.00 m/s
Distance d=25.0 m
Force F=30.0 N
From work-energy theorem we know that the work done equals the change in kinetic energy
W=ΔK=Kf-Ki=1/2mvf²-1/2mvi²
And

So

and we know that the force the sprinter exerted Fsprinter the force of the headwind Fwind=30.0N
So
Answer: A
Explanation: isotopes of the same thing element have the same number of protons in the nucleus but differ in the number of neutrons.
Answer:
w = 2w₀ the angular velocity of man doubles
Explanation:
In this exercise, releasing the weights reduces the moment of inertia
I= I₀ / 2
Therefore, since the platform system plus man is isolated, the kinetic moment must be conserved
L₀ = L
I₀ w₀ = I w
I₀ w₀ = I₀ / 2 w
w = 2w₀
therefore the angular velocity of man doubles
Answer:
Explanation:
Radius of the ball is 
Initial speed of the ball is 
Initial angular speed of the ball is 
Coefficient of kinetic friction between the ball and the lane
is 
Due to the presence of frictional force, ball moves with
decreasing velocity.
(a)
velocity
in terms of
is

(b)
Ball's linear acceleration is given by

(c)
During sliding, ball's angular acceleration is calculated as

(d)
The time for which the ball slides is calculated from the
equation of motion is

(e)
Distance traveled by the ball is

(for)
The speed of the ball when smooth rolling begins is
