Question

I need help with these. Please show workings
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Answer 1

Hey There!

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Question 1)

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DATA:

Force = F = 5N

time = t = 5 seconds

mass = m = 5 kg

momentum = p = ?

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SOLUTION:

IMPULSE FORCE:

The force which acts for a very short period of time is called impulse force. It is given by,

I = F x t

Where,

I is impulse

F is force

t is time till which force is exerted

The impulse experienced by the object equals the change in momentum of the object. In equation form,

F x t = M x ΔV

So,

F x t = Final momentum - initial momentum

F x t = final momentum - (0)

initial momentum is zero because the object was initially at rest.

Final momentum = 5 x 5

Final momentum = 25
`kgms^(-1)`

So B is the answer

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Question 2)

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DATA:

Force = F = 30 N

time = t = 0.05 seconds

mass = m = 0.075 kg

V = ?

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SOLUTION:

impulse force is given by,

I = F x t

Where,

I is impulse

F is force

t is time till which force is exerted

The impulse experienced by the object equals the change in momentum of the object. So,

F x t = M x ΔV

So,

F x t = Final momentum - initial momentum

F x t = final momentum - (0)

Since it was at rest initially, initial momentum is zero.

Momentum is given by,

p = m x V

where,

p is momentum

m is mass

v is velocity

So,

F x t = m x V

Rearrange the equation,

V =
`(Fxt)/(m)`

`V = ((30)x(0.05))/(0.075) \\\\V = 20 m/s`

So C is the answer

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Best Regards,

'Borz'

Answer 2

Imp = 25 [kg*m/s]

v₂= 20 [m/s]

Step-by-step explanation:

In order to solve these problems, we must use the principle of conservation of linear momentum or momentum.

1)

`(m_(1)*v_(1))+(F*t)=(m_(1)*v_(2))`

where:

m₁ = mass of the object = 5 [kg]

v₁ = initial velocity = 0 (initially at rest)

F = force = 5 [N]

t = time = 5 [s]

v₂ = velocity after the momentum [m/s]

`(5*0) +(5*5) = (m_(1)*v_(2)) = Imp\\Imp = 25 [kg*m/s]`

2)

`(m_(1)*v_(1))+(F*t)=(m_(1)*v_(2))\\(0.075*0)+(30*0.05)=(0.075*v_(2))\\v_(2)=20 [m/s]`