Answer: The correct option is Option b.
Explanation:
Power is defined as the rate of work done by an object.
Mathematically,
.....(1)
And work done is the product of force exerted on the object times the displacement covered by that object.
Mathematically,

Putting this value in above equation, we get:

where,
P = power = ?W
F = Force exerted = 10N
s = Displacement = 400cm = 4m (Conversion factor: 1m = 100 cm)
t = Time taken = 8s
Putting values in above equation, we get

Hence, the correct option is Option b.
<h2>
<u>Required</u><u> </u><u>Answer</u><u>:</u></h2>
The body will <u>stay at rest </u>(Option D). It is because a force of magnitude 50 N is pulled towards left and another force is pulling it towards right with same magnitude 50 N. So, the direction of force is opposite and magnitude is same i.e. 50 N. So, they will cancel each other and net force is 0. Hence, there would be no acceleration.
- Option A - Showing acceleration
- Option B - Showing acceleration
- Option C - Change of direction due to Net force
Hence, these options are incorrect because they are only possible when net external force is non-zero. Staying at rest i.e. Option D means there is no motion and hence no acceleration, this shows that net force is 0
<u>━━━━━━━━━━━━━━━━━━━━</u>
The SI unit for velocity and speed is meters per second
Upper fixed point is a temperature of stem from water boiling and standards atmospheric pressure
Lower fixed point is the temperature of pure melting ice.