Answer:
Explanation:
Two straight wires
Have current in opposite direction
i1=i2=i=2Amps
Distance between two wires
r=5mm=0.005m
Length of one wire is ∞
Length of second wire is 0.3m
Force between the wire,
The force between two parallel currents I1 and I2, separated by a distance r, has a magnitude per unit length given by
F/l = μoi1i2/2πr
F/l=μoi²/2πr
μo=4π×10^-7 H/m
The force is attractive if the currents are in the same direction, repulsive if they are in opposite directions.
F/l = μoi1i2/2πr
F/0.3=4π×10^-7×2²/2π•0.005
F/0.3=1.6×10^-4
Cross multiply
F=1.6×10^-4×0.3
F=4.8×10^-5N
Answer:

Given:
Initial velocity (u) = 30 m/s
Final speed (v) = 0 m/s
Acceleration (a) = - 1.5 m/,s²
To Find:
Time in which train will come to rest (t).
Explanation:

So,
Time in which train will come to rest = 20 seconds
Concaved lenses...........
Answer:
the change in momentum = Force x change in time