The car at 60 kph has 9 times more kinetic energy than the car traveling at 20 kph. This assumes that both cars have the same mass. Kinetic energy depends on the square of thee speed so if one car is going 3 times faster, its kinetic energy will be 3^2 ( = 9 ) greater. The car going at 60 kph will have 4 times the KE of the car going at 30 kph ( again assuming that the cars have the same mass.)
Electromagnets have certain advantages over permanent magnets. One of the major advantage is, the amount of electric current can easily be controlled, in turn, magnetic field can be controlled. Out of all the options, option D would be the best answer.
In short, Your Answer would be option D) Electromagnets can easily be turned on and off.
Hope this helps!
Answer:
1.10m/s
2.0.1m
3.5Hz
Explanation:
v=velocity, f=frequency and T=wavelength
1.v=ft
v=2x5
=10m
2.v=ft
100=1000T
divide both sides by 1000
T=0.1m
3.v=fT
25=5f
divide both sides by 5
f=5Hz
Answer:
film is at distance of 3.07 cm from lens
Explanation:
Given data
focal length = 3.06 cm
distance = 10.4 m = 1040 cm
to find out
How far must the lens
solution
we apply here lens formula that is
1/f = 1/p + 1/q
here f = 3.06 and p = 1040 so we find q
1/f = 1/p + 1/q
1/3.06 = 1/1040 + 1/q
1/ q = 0.3258
q = 3.0690 cm
so film is at distance of 3.07 cm from lens
10m long is the right answer or 16
