d 30 minutes a day , 5 days a week
<h3><u>Answer;</u></h3>
B. 16.2 m/s
<h3><u>Explanation</u>;</h3>
Using the equation;
v = u + at; where v is the final velocity, u is the initial velocity, a is the acceleration and t is the time taken;
u = 21 m/s, a= -2.4 m/s^2 and t = 2 seconds
Therefore;
v = 21 + ((-2.4) × 2)
= 21 - 4.8
<u> = 16.2 m/s</u>
Answer:
changes
Explanation:
According to Michael Faraday, voltage is induced on a metallic conductor when the magnetic field changes. The principle is known as the principle of electromagnetic induction. The voltage induced on the metallic conductor is referred to as induced emf.
The magnitude if induced emf depends on the rate of change of the magnetic flux.
Net force can be defined as the sum of force acting on an object in all the directions
.i.e Net force= F acting on a body at upward direction+ F at downward direction+ F at leftward direction+ F at rightward direction.
e.g if a body is at rest the sum of forces acting on body in all direction is zero
but if a body is moving its mean body is facing an unbalanced net force.
Answer:
The minimum power the motor would need is 2035 Watts.
Explanation:
the minimum power motor needed is given by the total work done on the load, Wtot and the total time it takes the load to be lifted, given by:
P = Wtot/t
the forces doing works on the load is the gravitational force, Wfg and the frictional force, Wf the total work done on the load is:
Wtot = Wfg + Wf
= m×g×d + f×d
= d×(m×g + f)
= (30)×(200×9.8 + 75)
= 61050 J
it takes t = 30s for the load to be lifted high the building, the minimum power neeed is then:
P = Wtot/t
= (61050)/(30)
= 2035 Watts
Therefore, the minimum power the motor would need is 2035 Watts.