The answer is 40 J. <span>A student pulls a lever down 4 m. The lever lifts a box that weighs 20 N up a distance of 2 m. 40 J of work was done on the box. </span>
Answer:
-0.67
Explanation:
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(final velocity minus initial velocity) divided by time
Answer:
The emf, electric field and the current in the wire are 10 V, 3.57 V/m and 1.43 A.
Explanation:
Given that,
Resistance = 7 ohms
Length = 2.8 m
Time t =0.2
We need to calculate the change in magnetic flux
Using formula of induced emf
Put the value into the formula
We need to calculate the electric field in the wire
Using formula of electric field
We need to calculate the current in the wire,
Using formula of ohm's law
Put the value into the formula
Hence, The emf, electric field and the current in the wire are 10 V, 3.57 V/m and 1.43 A.
Answer:
0.426 volts
Explanation:
It is given that,
The radius of a circular loop, r = 11.2 cm = 0.112 m
An elastic conducting material is stretched into a circular loop.
It is placed with its plane perpendicular to a uniform 0.880 T magnetic field.
The radius of the loop starts to shrink at an instantaneous rate of 68.8 cm/s, dr/dt = 0.688 m/s
We need to find the emf induced in the loop at that instant.
So, the magnitude of induced emf is 0.426 volts.