Answer:
F = 7.143 kN
Explanation:
given,
time taken to apply break = 1.05 s
car slows down from 15 m/s to 9 m/s
mass of the car = 1250 Kg
force is equal to the change in momentum with respect to time.
F = -7142.85 N
F = - 7.143 kN
Force is acting opposite direction of velocity of car i.e. the sign is negative.
I think it's 0J because the man doesn't move the car.
W = F*d
W = 9000*0 (the car didn't move)
W = 0J
Answer:
Increases.
Explanation:
The electric potential increases when the two positive charges of same magnitude bring close to one charge to another because there is repulsive force between them due to same charge and when the two opposite charges move away from each other, the potential energy decreases. When two opposite charges are brought closer together, electric potential energy decreases while on the other hand, when we move opposite charges apart from each other than the work done against the attractive force that leads to an increase in electric potential energy.
Answer:
Explanation:
Let v be the terminal velocity of the bar .
emf induced in the bar of length L
= B L v where B is the value of magnetic field.
current i in the circuit containing resistance R
i = induced emf / R
BLv / R
Magnetic force in upward direction in the bar
F = BiL
= BL x BLv / R
B²L²v / R
For attainment of uniform velocity
magnetic force = weight
B²L²v / R = mg
so current
i = BLv / R
A. Tree
B. Shapes
C. Grass
D. Mehndi