Answer:
hmax = 1/2 · v²/g
Explanation:
Hi there!
Due to the conservation of energy and since there is no dissipative force (like friction) all the kinetic energy (KE) of the ball has to be converted into gravitational potential energy (PE) when the ball comes to stop.
KE = PE
Where KE is the initial kinetic energy and PE is the final potential energy.
The kinetic energy of the ball is calculated as follows:
KE = 1/2 · m · v²
Where:
m = mass of the ball
v = velocity.
The potential energy is calculated as follows:
PE = m · g · h
Where:
m = mass of the ball.
g = acceleration due to gravity (known value: 9.81 m/s²).
h = height.
At the maximum height, the potential energy is equal to the initial kinetic energy because the energy is conserved, i.e, all the kinetic energy was converted into potential energy (there was no energy dissipation as heat because there was no friction). Then:
PE = KE
m · g · hmax = 1/2 · m · v²
Solving for hmax:
hmax = 1/2 · v² / g
Answer:
Explanation:
When the screw is turned by two turns then change in the length of the wire is given as
now we know by the formula of Young's modulus
so we have
Answer: 5.76 rads/s
Explanation:
The initial rotation is 55 rpm
1 rev = 2π radians
55 revs = 55 × 2π/1 = 345.58 radians/min
345.58 rads/min = 345.58rads/60s = 5.76 rads/s
Answer:
Charge enter a 0.100 mm length of the axon is 
Explanation:
Electric field E at a point due to a point charge is given by
where 
is the constant =
is the magnitude of point charge and 
is the distance from the point charge
Charges entering one meter of axon is 
Charges entering 0.100 mm of axon is 
substituting the value of 
in above equation, we get charge enter a 0.100 mm length of the axon is
Answer: 2.72 metres
Explanation:
Given that:
frequency of sound F = 123 Hz. wavelength of sound in the air = ?
speed of sound in air V = 334 m/s
Recall that wavelength is the distance covered by the wave after one complete cycle. It is measured in metres, and represented by the symbol λ.
So, apply V = F λ
λ = V /F
λ = 334m/s / 123Hz
λ = 2.72m
Thus, the wavelength of this sound in the air is 2.72 metres
