Answer:
Average power output of athlete = 11025 Watts
Explanation:
Work done is defined as the product of force applied and the displacement perpendicular to the force.
Work = 
Power is defined as work done per unit time.
Power = 
Here the person lifts 900 kg.
Height = 2.5 m
Time interval = 2 seconds
Force = 
= 
= 8820 N
Work done = 
= 
= 22050 J
Power = 
= 11025 Watt
Answer:
(a) Height is 4.47 m
(b) Height is 4.37 m
Solution:
As per the question:
Initial velocity of teh ball, 
Angle made by the ramp, 
Distance traveled by the ball on the ramp, d = 5.00 m
Now,
(a) At any point on the projectile before attaining maximum height, the velocity can be given by the eqn-3 of motion:

where
H =
g = 

= 19.06 m/s
Now, maximum height attained is given by:


Height from the ground = 
(b) now, considering the coefficient of friction bhetween ramp and the ball,
:
velocity can be given by the eqn-3 of motion:


= 18.7 m/s
Now, maximum height attained is given by:


Height from the ground = 
Answer:
k = 5178.8 N/m
Explanation:
As we know that spring mass system will oscillate at angular frequency given as

now we have

now the maximum acceleration of the spring block system is at its maximum compression state which is given as

here A= maximum compression of the spring
so here in order to find maximum compression of the spring we will use energy conservation as we know that initial total kinetic energy of the car will convert into spring potential energy

here we know that
v = 85 km/h

now we have


now from above equation of acceleration we have



Answer:
The coefficient of kinetic is

Explanation:
The forces in the axis 'x' and 'y' using law of Newton to find coefficient of kinetic friction
ΣF=m*a
ΣFy=W-N=0
ΣFy=Fn-Fu=m*a


Now to find the coefficient can find the acceleration using equation of uniform motion accelerated

So replacing the acceleration can fin the coefficient:
