Question

a girl if a girl if mass 40 kg sit on a trolley of mass 5kg the initial speed of the trolley is 5 metre per second when a force is applied the trolley comes to the rest after travelling a distance of 10 metres first find the work done of the trolley second find the work done by the girl on the trolley.​

Answer 1

Given :-

Mass of the girl = 40 kg

Mass of the trolley = 5 kg

Initial velocity of the trolley = 5 m/s

Final velocity of the trolley = 0 m/s

Distance covered = 10 m

To Find :-

The work done of the trolley.

The work done by the girl on the trolley.​

Analysis :-

Firstly find the total mass by adding both mass of girl and trolley.

Then using the third equation of motion find the acceleration accordingly by substituting the given values.

Then using the formula of force you can easily find the rest.

Solution :-

Total mass,

Total mass = m₁ + m₂

= 40 + 5

= 45 kg

We know that,

• v = Final velocity
• a = Acceleration
• s = Displacement
• u = Initial velocity

Using the formula,

$\underline{\boxed{\sf Third \ equation \ of \ motion=2as=v^2-u^2}}$

Given that,

Displacement (s) = 10 m

Final velocity (v) = 0 m/s

Initial velocity (u) = 5 m/s

Substituting their values,

⇒ 2 × a × 10 = 0² - 5²

⇒ 20a = 0 - 25

⇒ 20a = -25

⇒ a = -25/20

⇒ a = -1.25 m/s

We know that,

• f = Force
• a = Acceleration
• m = Mass

Using the formula,

$\underline{\boxed{\sf Force=Mass \times Acceleration}}$

Given that,

Mass (m) = 45 kg

Acceleration (a) = -1.25 m/s

Substituting their values,

⇒ f = ma

⇒ f = 45 × (-1.25)

⇒ f = -56.25 N

We know that,

• f = Force
• w = Work done
• s = Displacement

Using the formula,

$\underline{\boxed{\sf Work \ done=Force \times Displacement}}$

Given that,

Force (f) = -56.25 N

Displacement (s) = 10 m

Substituting their values,

⇒ w = fs

⇒ w = -56.25 × 10

⇒ w = -562.5 J

Therefore, the work done by the trolley is -562.5 J.

A.T.Q,

Since the girl does not move w.r.t. the trolley (as she is sitting on the trolley), work done by the girl would be 0 J.

Answer 2

Answer:

the work done by trolley = -562.5 J

the work done by the girl = 0 as she has been sitting doing nothing

Explanation:

Given:

• Mass of the girl = 40 kg

• Mass of trolley = 5 kg

• Initial speed of the trolley = 5 metre per/sec

• Velocity of trolley =  0 metre/sec

• Total distance covered = 10 metres

To FiND:

• The work done of the trolley

• The work done by the girl on the trolley

SolutioN:

Total mass = m₁ + m₂

= 40 + 5

= 45 kg

The formula used :

2as = v² - u²

Given,

Displacement = 10m

Intial velocity = 5 metre/s

Final velocity = 0 metre/s

Now, to substitue their values,

f = ma

f = 45 * (-1.25)

f = -56.25 N

The formula used :

Displacement * Force

f = -56.25 N

Displacement = 10m

Now, to substitue their values

w = fs

w = -56.25 * 10

w = -562.5 J

AnswER:

the work done by trolley = -562.5 J

the work done by the girl = 0 as she has been sitting doing nothing

HOPE IT HELPS!! PLZ MARK ME AS BRAINLIEST