Answer:
onservation of energy
U top = K bottom
(m + m)*g*L = 1/2*I*?^2 where I = m*(L/2)^2 + m*L^2 = 1.25*m*L^2
So 2m*g*L = 1/2*1.25*m*L^2*?^2
So ? = sqrt(3*g*/(1.25*L) ) = sqrt(12g/5L)
The average force applied to the ball= 106.7 N
Explanation:
Force is given by
f= ΔP/t
ΔP= change in momentum= m Vf- m Vi
m= mass =0.2 kg
Vf= final velocity= 12 m/s
Vi=initial velocity= -20 m/s ( negative because it is going towards the wall which is treated as negative axis)
t= time= 60 ms= 0.06 s
now ΔP= 0.2 [ 12-(-20)]
ΔP=0.2 (32)=6.4 kg m/s
now force F= ΔP/t
F= 6.4/0.06
F=106.7 N
Answer:
Explanation:
The energy of Mass-Spring System the sum of the potential energy of the block plus the kinetic energy of the block:

Where:

There are two cases, the first case is when the spring is compressed to its maximum value, in this case the value of the kinetic energy is zero, since there is no speed, so:

The second case is when the block passes through its equilibrium position, in this case the elastic potential energy is zero since
, so:

Now, let's find the energy of the system when the block is replaced by one whose mass is twice the mass of the original block using the previous data:

Where in this case:

Therefore:

Answer:
The current of the outer coil is 
Explanation:
From the question we are told that
The number of turns of the inner coil is 
The radius of the inner coil is
The current of the inner coil is 
The number of turns of the outer coil is 
The radius of the outer coil is 
Generally the net magnetic field is mathematically represented as

Now from told that the net magnetic field is common
So

Here
is the permeability of free space
making
the subject

substituting values


The last one with the guy in the light yellow shirt