Question

It was once recorded that a Jaguar left skid marks that were 290 m in length. Assuming that the
Jaguar skidded to a stop with a constant acceleration of -3.90 m/s2 , determine the speed of the Jaguar
before it began to skid.

Answer 1

Answer :-

Speed of the Jaguar before it began to skid is 47.56 m/s .

Explanation :-

We have :-

→ Length of skid marks = 290 m

→ Acceleration of the jaguar = - 3.90 m/s²

• Since the jaguar finally stops by skidding, so it's final velocity will be zero.

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Now, according to the 3rd equation of motion :-

v² - u² = 2as

Where :-

• v is the final velocity.

• u is the initial velocity

• a is the acceleration.

• s is distance.

Substituting values, we get :-

⇒ 0 - u² = 2(-3.90)(290)

⇒ - u² = - 2262

⇒ u² = 2262

⇒ u = √2262

⇒ u = 47.56 m/s

Answer 2

Answer:

Given :-

• It was once a recorded that a Jaguar left skid marks that were 290 m in length.
• The Jaguar skidded to stop with a constant acceleration of - 3.90 m/s².

To Find :-

• What is the speed of the Jaguar before it began to skid.

Formula Used :-

$\clubsuit$ 3rd Equation of Motion :

$\longmapsto \sf\boxed{\bold{\pink{v^2 - u^2 = 2as}}}$

where,

• v = Final Velocity
• u = Initial Velocity
• a = Acceleration
• s = Distance Covered

Solution :-

Given :

$\bigstar$ Distance Covered (s) = 290 m

$\bigstar$ Acceleration (a) = - 3.90 m/s²

$\bigstar$ Final Velocity (v) = 0 m/s

According to the question by using the formula we get,

$\implies \sf (0)^2 - u^2 =\: 2 \times (- 3.90) \times 290$

$\implies \sf 0 - u^2 =\: 2 \times \bigg(- \dfrac{390}{100}\bigg) \times 290$

$\implies \sf - u^2 =\: 2 \times \bigg(- \dfrac{1131\cancel{00}}{1\cancel{00}}\bigg)$

$\implies \sf - u^2 =\: 2 \times \bigg(- \dfrac{1131}{1}\bigg)$

$\implies \sf - u^2 =\: 2 \times (- 1131)$

$\implies \sf {\cancel{-}} u^2 =\: {\cancel{-}} 2262$

$\implies \sf u^2 =\: 2262$

$\implies \sf u =\: \sqrt{2262}$

$\implies \sf u =\: 47.56$

$\implies \sf\bold{\red{u =\: 47.56\: m/s}}$

$\therefore$ The speed or initial velocity of the Jaguar before it began to skid is 47.56 m .