Question

it was one recorded that a jaguar left skid marks that were 290m in length assuming that the jaguar skidded to a stop with a constant acceleration of _3.90 meter per second square ,determine the speed of the jaguar before it begin to skid

Answer 1

$\checkmark$ Given:

It was once recorded that a Jaguar left skid marks that were 290 m in

length. Assuming that the jaguar skidded to stop with a constant

acceleration of  -3.90 m/s²

$\checkmark$ To Find:

The speed of the jaguar before it begin to skid

$\checkmark$ Solution:

We know that,

$\red{\bigstar \ \boxed{\rm v^{2}=u^{2}+2as}}$

Here,

• u = initial velocity
• v = final velocity
• a = acceleration
• s = distance

UNITS:

• u = m/s
• v = m/s
• a = m/s²
• s = m

Here,

• m = metre
• s = second

According to the Question,

We are asked to find the speed of the jaguar before it begin to skid

So, we must find "u"

Given that,

It was once recorded that a Jaguar left skid marks that were 290 m in

length. Assuming that the jaguar skidded to stop with a constant

acceleration of  -3.90 m/s²

Hence,

• s = 290 m
• a = -3.90 m/s²
• v = 0 m/s [comes to rest]

By Substituting the values,

We get,

$\blue{\rm \implies 0^{2}=u^{2}+2 \times -3.90 \times 290}$

$\green{\rm \implies 0=u^{2}-2262}$

$\orange{\rm \implies -u^{2}=-2262}$

Cancelling negative sign on both sides,

We get,

$\red{\rm \implies u^{2}=2262}$

Taking square root,

We get,

$\blue{\rm \implies u=\sqrt{2262} \ m/s}$

$\green{\rm \implies u=47.56 \ m/s}$

On Approximation,

We get,

$\pink{\rm \implies u \approx 48 \ m/s}$

Hence,

The speed of the Jaguar before it begins to skid is 48 m/s

Answer 2

Question:-

It was one recorded that a jaguar left skid marks that were 290m 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 begin to skid.

Formula used:-

v² = u² + 2as

where,

• v is final velocity (m/s)
• u is initial Velocity (m/s)
• a is acceleration (m/s²)
• s is Displacement (m)

Answer:-

Given:

• v = 0m/s (as it comes to rest)
• u = ?
• a = -3.9 m/s²
• s = 290m

Putting in the values

v² = u² + 2as

=> 0² = u² + (2 * -3.9 * 290)

=> 0 = u² - 2262

=> 2262 = u²

=> u = √(2262)

=> u = 47.56 m/s

So, u = velocity of the jaguar before it begin to skid = 47.56m/s

Ans. 47.56m/s