A force of 200 N acts on a body of mass 20 kg. The force accelerates the body from rest until it attains a velocity of 50 ms−1. Through what distance does the force act?
1 25,000 m
2 125 m
3 4,000 m
4 250 m
Answers
Answer:
2) 125 m
Explanation:
- Force (F) = 200 N
- Mass (m) = 20 kg
- Initial velocity (u) = 0 m/s [As started from rest]
- Final velocity (v) = 50 m/s
- Distance (s) = ?
We know, Force = mass × acceleration. Let's find acceleration first !
200 = 20 × a
Now, we remember Newton's first equation of motion i.e, v = u + at. By this equation we can find the time taken.
50 = 0 + 10 × t
Now, we also remember Newton's second equation of motion i.e,
Finally put all the values for distance.
s = 0 + 5 × 25
☆ QuestioN
A force of 200 N acts on a body of mass 20 kg. The force accelerates the body from rest until it attains a velocity of 50 ms−1. Through what distance does the force act?
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☆ AnsWer
125 m is the distance.
given:
- force = 200 N
- mass = 20 kg
- initial velocity = 0 m/s as it was at rest .
- final velocity = 50m/s
to find:
distance = ?
first we need to find the acceleration .
we know that F = m × a ( m is mass and a is acceleration , F is force.)
by using this,
F = m × a
200 = 20 × a
a = 200/20
a = 20/2
a = 10 m/s²
Therefore acceleration is 10 m/s²
Now we have to find the time taken.
we know that by Newton's first equation of motion,
V = u + at
50 = 0 + 10t
50 = 10t
t = 50/10
t = 5 s
therefore time take is 5 s
From second equation of motion,
we know that ,
s = u + ½at²
= 0 + ½ × 10 × 5²
= ½ × 10×25
= 5 × 25
= 125 m
therefore 125 m is the distance