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1 year ago

Worth 25 points on my exam

Physics

2 answers:

I am Lyosha [343]1 year ago

7 0

Initial velocity=20m/s
Final velocity=0m/s(As the car stops)
Acceleration=-8m/s^2
Distance=s=26m

We need to verify the thrid equation of kinematics here

$\\ \tt\longmapsto v^2-u^2=2as$

$\\ \tt\longmapsto 20^2=2(-8)s$

$\\ \tt\longmapsto 400=-16s$

$\\ \tt\longmapsto s=|400/-16|$

$\\ \tt\longmapsto s=25m$

The squirrel has a good luck ,Car gets stopped just 1m away from the squirrel .

dedylja [7]1 year ago

6 0

Explanation:

<u>According</u><u> to</u><u> the</u><u> Question</u>

A squirrel runs out in front of a car moving at +20m/s ( initial speed u) . The driver slams on the brakes and begins decreasing at -8m/s² ( here the acceleration is acting in opposite directions of motion a )

When Squirrel was 26 metres ( Distance from the car initially )

Using Kinematic Equation

v² = u² + 2as

On substituting the value we obtain

➥ 0² = 20² + 2 × -8 × s

➥ 0 = 400 - 16 × s

➥ -400 = -16 × s

➥ 400/16 = s

➥ 25 = s

So, the squirrel is 25 metres from the car .

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<h3>Answer</h3>

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Putting values in above equation, we get:

$q=165g\times 4.184J/g.^oC\times 77^oC\\\\q=53157.72J$

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To calculate the number of photons, we divide the total energy by energy of one photon, we get:

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Putting values in above equation, we get:

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