Answer:
25000 V
Explanation:
The formula for potential is
V = Kq/r
Potential at B due to the charge placed at origin O
V1 = K q / OB

V1 = 10000 V
Potential at B due to the charge placed at A
V2 = K q / AB

V2 = 15000 V
Total potential at B
V = V1 + V2 = 10000 + 15000 = 25000 V
The only function of the pulleys in the diagram is to change the direction
of the force applied to raise the bricks.
<h3>What is a Pulley?</h3>
A pulley is a wheel which has a flexible rope on its rim and helps to
transmit energy and motion.
In the diagram given, we can see that the pulley is used to raise a mass of
block by three people. They pull the rope horizontally in order to raise the
block vertically. This means that it was used to change the direction of the
applied force.
Read more about Pulley here brainly.com/question/177456
Explanation:
momentum = mass x velocity
initial momentum = 100 x 15 = 1500kgm/s
after momentum = 100 x 20 = 2000kgm/s
a =(v-u)/t
a = (20-15)/10
a = 5/10
a = 0.5m/s²
f = ma
f = 100 x 0.5
f = 50N
Moons gravity is about 1/6 as powerful as it is on Earth, so about 20 pounds.
Answer:

Explanation:
given data:
refractive index of lens 1.50
focal length in air is 30 cm
focal length in water is -188 cm
Focal length of lens is given as
![\frac{1}{f} =\frac{n_2 -n_1}{n_1} * \left [\frac{1}{r1} -\frac{1}{r2} \right ]](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bf%7D%20%3D%5Cfrac%7Bn_2%20-n_1%7D%7Bn_1%7D%20%2A%20%5Cleft%20%5B%5Cfrac%7B1%7D%7Br1%7D%20-%5Cfrac%7B1%7D%7Br2%7D%20%20%20%5Cright%20%5D)
![\frac{1}{f} =\frac{n_{g} -n_{air}}{n_{air}} * \left [\frac{1}{r1} -\frac{1}{r2} \right ]](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bf%7D%20%3D%5Cfrac%7Bn_%7Bg%7D%20-n_%7Bair%7D%7D%7Bn_%7Bair%7D%7D%20%2A%20%5Cleft%20%5B%5Cfrac%7B1%7D%7Br1%7D%20-%5Cfrac%7B1%7D%7Br2%7D%20%20%20%5Cright%20%5D)
![\frac{1}{f} =\frac{n_{g} -1}{1} * \left [\frac{1}{r1} -\frac{1}{r2} \right ]](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bf%7D%20%3D%5Cfrac%7Bn_%7Bg%7D%20-1%7D%7B1%7D%20%2A%20%5Cleft%20%5B%5Cfrac%7B1%7D%7Br1%7D%20-%5Cfrac%7B1%7D%7Br2%7D%20%20%20%5Cright%20%5D)
focal length of lens in liquid is
![\frac{1}{f} =\frac{n_{g} -n_{l}}{n_{l}} * \left [\frac{1}{r1} -\frac{1}{r2} \right ]](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bf%7D%20%3D%5Cfrac%7Bn_%7Bg%7D%20-n_%7Bl%7D%7D%7Bn_%7Bl%7D%7D%20%2A%20%5Cleft%20%5B%5Cfrac%7B1%7D%7Br1%7D%20-%5Cfrac%7B1%7D%7Br2%7D%20%20%20%5Cright%20%5D)

rearrange fro


