Answer:
B = 0.75 T
Explanation:
As we know that the force on a moving charge in magnetic field is given by the formula

here we have

here we know that



now from above equation we have


We will define the Total mass to calculate the force, so our values are:
Total Mass 
The Weight is,

Through the hook's Law we calculate X.
, where x is the lenght of compression and K the Spring constant.
We don't have a K-Spring, but we can assume a random value (or simply let the equation in function of K)

I assume a value of 

Answer:
20 watts
Explanation:
Big brain mode activated:
Power=1200J/60sec
Power=20 watts
From rest, a rock is dropped from a garage roof. The roof is 6.0 meters above ground level. The rock will reach the earth at a speed of 10.849 meters per second.
<h3>What is velocity?</h3>
The change of displacement with respect to time is defined as the velocity. Velocity is a vector quantity.
it is a time-based component. Velocity at any angle is resolved to get its component of x and y-direction.
Given data:
V(Final velocity)=? (m/sec)
h(height)= 6.0 m
u(Initial velocity)=0 m/sec
g(gravitational acceleration)=9.81 m/s²
Newton's third equation of motion:

Hence, the velocity of the rock as it hits the ground will be 10.849 m/sec.
To learn more about the velocity refer to the link ;
brainly.com/question/862972
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