Question

a motorcycle us moving with a velocity of 90 km/hr and it takes 5 seconds to stop after the brakes applies. calculate the force exerted by the brakes on the motorcycle if it's mass along with the rider is 200kg


plz answer ​

Answer 1

CORRECT QUESTION :-

★ A motorcycle is moving with a velocity of 90 km/h and it takes 5 seconds to stop after the brake applies. Calculatethe force exerted by the brakes on motorcycle if its mass along with the rider is 200 kg.

GIVEN :-

• Initial velocity , u = 90 km/h.
• Final velocity , v = 0 m/s.
• Time , t = 5 seconds.
• mass of body , m = 200 kg.

TO FIND :-

• The force exerted by the brakes on motorcycle , F.

SOLUTION :-

★ Firstly we will convert the initial velocity in m/s.

→ initial velocity = 90 km/h

→ (90 × 1000)/3600

→ (90 × 10)/36

→ 900/36

→ Initial velocity = 25 m/s.

Now , As we know that,

→ Acceleration = (Final velocity - Initial velocity)/Time

→ a = (v - u)/t

→ a = (0 - 25)/5

→ a = -25/5

→ Acceleration = -5 m/s².

Note :- The negative sign (-ve) indicates retardation of Acceleration.

Now as we know that,

→ Force = mass × Acceleration

→ F = ma

→ F = 200 kg × -5 m/s²

→ F = -1000 kg × m/s²

→ F = -1000 N.

Hence The force exerted by the brakes on motorcycle is (-1000) Newtons.

Answer 2

$\huge\bf{\pink{\underline{\underline{\purple{QUESTION:-}}}}}$

☃️ A motorcycle is moving with a velocity of 90km/hr and it takes 5sec. to stop after the brakes are applies calculate the force exerted by the brakes on the motorcycle it's mass along the rider is 200 kg .

$\huge\bf{\pink{\underline{\underline{\purple{ANSWER:-}}}}}$

$\mathcal{\gray{\underbrace{\blue{GIVEN:-}}}}$

• A motorcycle is moving with a velocity = 90km/hr .

• Time taken to stop after the brakes applied = 5s

• Mass of motorcycle along with rider = 200kg

$\mathcal{\gray{\underbrace{\blue{TO\: FIND:-}}}}$

• The force exerted by the brakes on the motorcycle .

$\mathcal{\gray{\underbrace{\blue{CALCULATE:-}}}}$

⭐ Here, the final velocity (v) of the motorcycle is “ 0 ” . [Bcz, brakes are applied on the motorcycle .]

• initial velocity (u) = 90km/h = 90 × 5/18 = 25m/s

• Time (t) = 5s

$\orange\bigstar\:\rm{\gray{\overbrace{\underbrace{\pink{v\:=\:u\:+\:at\:}}}}}$

$\rm{\implies\:0\:=\:25\:+\:a\times{5}\:}$

$\rm{\implies\:a\times{5}\:=\:-25\:}$

$\rm{\implies\:a\:=\:\dfrac{-25}{5}\:}$

$\rm{\green{\implies\:a\:=\:-5\:m/s^2}}$

[Note :- The -ve sign indicates the deacceleration of the motorcycle.]

⭐ According to Newton's 2nd law motion ,

$\red\bigstar\:\rm{\gray{\overbrace{\underbrace{\pink{Force\:=\:mass\times{acceleration}\:}}}}}$

• mass = 200kg

$\rm{\implies\:F\:=\:200\times{-5}\:}$

$\rm{\green{\implies\:F\:=\:-1000\:N}}$

$\rm\pink{\therefore}$ The force exerted by the brakes is “ 1000N ” .