Answer:
Explanation:distance-time =speed
a,V =s/t
V=2m/2s
V=1m/s
b,v=s/t
V=80m/40s
V= 2m/s
The average speed is 2m/s
Answer:
10.2 Watt
Explanation:
= number of turns in flat coil = 160
= area = 0.20 m²
B₀= initial magnetic field = 0.40 T
= final magnetic field = - 0.40 T
Change in magnetic field is given as
ΔB = B - B₀ = - 0.40 - 0.40 = - 0.80 T
= time taken for the magnetic field to change = 2.0 s
Induced emf is given as


= 12.8 volts
= Resistance of the coil = 16 Ω
Power is given as


= 10.2 Watt
The needle on a compass always points in the direction of magnetic north because of the magnetic poles of earth. the compass is essentially a magnet itself, so the southern pole of the compass is attracted to the northern pole of earth.