Answer:
energy per unit charge
Explanation:
EMF is energy per unit charge and has unit joule/ coulomb, where joule is unit of energy and coulomb is the unit of charge.
Answer:
A. it's the only answer that makes sense. if I'm wrong sorry
Answer:
Part a)

Part b)

Explanation:
Diameter of the circle = 24 ft
Diameter = 731.52 cm = 7.3152 m
now the horse complete 144 trips in one hour
so time to complete one trip is given as


now the speed of the horse is given as



Part a)
Now we know that the power is defined as rate of work done
it is given as




Part b)
Work done to climb up to 3 m height is given by

now we have




now we know that 1 HP = 746 Watt
so we have

Answer:
Explanation:
Given a parallel plate capacitor of
Area=A
Distance apart =d
Potential difference, =V
If the distance is reduce to d/2
What is p.d
We know that
Q=CV
Then,
V=Q/C
Then this shows that the voltage is inversely proportional to the capacitance
Therefore,
V∝1/C
So, VC=K
Now, the capacitance of a parallel plate capacitor is given as
C= εA/d
When the distance apart is d
Then,
C1=εA/d
When the distance is half d/2
C2= εA/(d/2)
C2= 2εA/d
Then, applying
VC=K
V1 is voltage of the full capacitor V1=V
V2 is the required voltage let say V'
Then,
V1C1=V2C2
V × εA/d=V' × 2εA/d
VεA/d = 2V'εA/d
Then the εA/d cancels on both sides and remains
V=2V'
Then, V'=V/2
The potential difference is half when the distance between the parallel plate capacitor was reduce to d/2
The complete question is;
James Joule (after whom the unit of energy is named) claimed that the water at the bottom of Niagara Falls should be warmer than the water at the top, 51 m above the bottom. He reasoned that the falling water would transform its gravitational potential energy at the top into thermal energy at the bottom, where turbulence brings the water almost to a halt. If this transformation is the only process occurring, how much warmer will the water at the bottom be?
Answer:
Water becomes warmer by a temperature of ΔT = 0.119 K
Explanation:
If we assume that gravitational kinetic energy will be converyrf into thermal enrgy, we will have;
Q = U
So, m•c_w•ΔT = mgh
Where;
c_w is specific heat capacity of water with a value of 4184 J/Kg.K
ΔT is change in temperature indicating how warmer the water will be. Thus making ΔT the subject, we have;
ΔT = gh/c_w
So, ΔT = 9.8 x 51/4184 = 0.119 K