(ii) Starting from rest, a body of mass 100 Kg attains velocity of 40 m/sec in 10 sec. find
the force acting on the body.
Answers
Given :
Initial velocity = zero
Mass of the body = 100kg
Final velocity = 40m/s
Time taken = 10sec
To find :
The force acting on the body.
Solution :
Firstly we have to find acceleration of the body, as we are provided with initial velocity, final velocity and time taken we can use first equation of motion that is,
v = u + at
where,
- v denotes final velocity
- u denotes Initial velocity
- a denotes acceleration
- t denotes time
by substituting all the given values in the equation,
➝ v = u + at
➝ 40 = 0 + (a)(10)
➝ 40 = 10a
➝ a = 40/10
➝ a = 4m/s²
Now, using second law of motion that is,
The rate of change of linear momentum of a body with time is proportional to the net external force acting on it .i.e.,
F = ma
where,
- F denotes force
- m denotes mass
- a denotes acceleration
by substituting the given values in the equation,
➝ F = ma
➝ F = (100)(4)
➝ F = 400N
thus, the force acting on the body is 400N.
Remember !
SI unit of froce is Newton (N).
SI unit of acceleration is metre per second square (m/s²).
Answer:
Given :
Initial velocity = zero
Mass of the body = 100kg
Final velocity = 40m/s
Time taken = 10sec
To find :
The force acting on the body.
Solution :
Firstly we have to find acceleration of the body, as we are provided with initial velocity, final velocity and time taken we can use first equation of motion that is,
v = u + at
where,
v denotes final velocity
u denotes Initial velocity
a denotes acceleration
t denotes time
by substituting all the given values in the equation,
➝ v = u + at
➝ 40 = 0 + (a)(10)
➝ 40 = 10a
➝ a = 40/10
➝ a = 4m/s²
Now, using second law of motion that is,
The rate of change of linear momentum of a body with time is proportional to the net external force acting on it .i.e.,
F = ma
where,
F denotes force
m denotes mass
a denotes acceleration
by substituting the given values in the equation,
➝ F = ma
➝ F = (100)(4)
➝ F = 400N..
thus, the force acting on the body is 400N.
Remember !
SI unit of froce is Newton (N).
SI unit of acceleration is metre per second square (m/s²).