Answer:
Explanation:
Distance of each of the charges from the center are equal . If this distance be d
d = .5 x length of diagonal of square
length of diagonal = 4√2
d = .5 x 4√2
= 2√2
potential at a point
V = k Q / r where k is a constant , Q is charge and r is distance of the point from the charge .
k = 9 x 10⁹
Total potential = 

= 
= 9 √2 x 10⁹ V .
Answer:
P = 11666.6 W
Explanation:
Given that,
Work done by the motor, W = 3500 kJ
Time, t = 5 min = 300 s
We need to find the power developed by the motor. Power developed is given by :

So, the required power is 11666.6 W.
Answer:
tire marks are due to the increase in thermal energy
Explanation:
When a tire is spinning at a given speed when the brakes are applied hard, the friction between the tire's particulate and the ground surface is high enough that some tire particles are transferred to the ground.
This is reflected in the heat transfer from the tire to the ground.
Consequently, tire marks are due to the increase in thermal energy and the change in the friction force of the tire.
Explanation:
Using Kinematics,
We have v = u + at.
=> v = (5m/s) + (2.0m/s²)(4.0s)
=> v = 13m/s.
Hence the child's speed is now 13m/s.