General Knowledge - Physics - Discussion

Discussion Forum : Physics - Section 1 (Q.No. 16)
16.
If two bodies of different masses, initially at rest, are acted upon by the same force for the same time, then the both bodies acquire the same
velocity
momentum
acceleration
kinetic energy
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
26 comments Page 2 of 3.

Atul kumar mishra said:   1 decade ago
According to the newton second law the rate of change of momentum is equal to force.

Mickei said:   1 decade ago
According to Newton's 2nd law: Rate of change of momentum = Force.

Mohammad Rafee Shaik said:   1 decade ago
Applied force is same.
Momentum=Mass*Velocity.

1st body velocity is high as mass is low.
2nd body velocity is low as mass is high.

Priyanka Boora said:   1 decade ago
According to newtons second law force is rate of change of momentum with time. So F=dp/dt.
We can write,
dp=f.dt.

So same force act for same time.
Hence momentum is same.

Faizan sabir said:   1 decade ago
Force = rate of change in momentum over time.
f= p/t.

Therefore p=f*t as per newton second law of motion states.

Mohan said:   1 decade ago
Momentum(p) = m*v.
p=f/a*v; since f=ma.
f=p/a*v; since a=v/t;.
f=p*t;.
Since time is constant, when we apply same force the momentum only changes.

Mansi said:   1 decade ago
F= ma.
Therefore a=F/m.

F is same in both cases but m is different therefore they can not have same acc.

Suppose,

Min first case be 2 and second case b 4. And force is 10 then in first case acc = 5 whereas in second case it is = 5/2. Which is not equal.

Now ke = 1/2 mv(square).
V = under root of ( 2 ke /m ).

Case 1 : m is 2 and ke is 10.
V =underfoot of (2*10/2)= underfoot 10.

Case 2 : M = 4 ke = 10

V = underfoot of (2*10/4) = under root of 5. Which is again not equal.
Then. V = ut + (1/2) at square in this case acc is changing again as v proved above therefore. It's not correct option.

And

Momentum.

P = f*t therefore both r constancent in ques. Therefore momentum is the answer.

Sanatan said:   1 decade ago
Here the velocity, acceleration and momentum all will be same for both the objects. How it could be only momentum?

Divyanshi said:   1 decade ago
We know that momentum = mass*velocity.

Even if we suppose that both acquire same velocity,

Then also the answer is not true as both have different masses.

Also among the given options, velocity is the only quantity which does not depend on mass and else other quantities do depend on mass.

k.e. = 1/2*mass*velocity square.

p = m*v.

Acceleration = force/mass.

So as a conclusion velocity should remain constant.

Rija Ali said:   1 decade ago
In this case momentum=m*v

Here v is 0 so if mass m1 is 3 and m2 is 4 but v is 0.

So momentum remains constant.


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