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Rudiy27
3 years ago
6

A 980-kg sports car travelling with a speed of 21 m/s collides into the rear end of a 2300-kg SUV that is stationary at a red li

ght. The bumpers lock, the brakes are locked, and the two cars skid forward a certain distance "d" before stopping (called stopping distance). The police officer estimates the coefficient of kinetic friction between tires and road to be 0.80. Calculate this stopping distance.
Physics
1 answer:
stiv31 [10]3 years ago
4 0

Answer:

Explanation:

After the collision , both the car will have common velocity , which according to conservation of momentum will be as follows

v = 980 x 21 / (980 + 2300)

= 20580 / 3280

= 6.274 m /s

The kinetic energy of both the cars after collision  

= 1/2 x (980+2300) x 6.274²

=  64555.44 J .

frictional force = μ mg where μ is coefficient of friction , mg is weight of both the cars

= .8 x (980+2300) x 9.8

= 25715.2 N

work done by friction will be equal to kinetic energy of car

25715.2 x d = 64555.44 ; where d is displacement of both the cars

d = 2.5  m

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Licemer1 [7]
<h2>It takes 6.78 seconds to complete 12 dribbles.</h2>

Explanation:

Frequency of dribble = 1.77 Hz

That is

         Number of dribbles in 1 second = 1.77

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Now we need to find how long does it take for you to complete 12 dribbles.

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3 years ago
Can someone help me?!!!!!
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<h2>Hello!</h2>

The answer is:

The first option,  the walker traveled 360m more than the actual distance between the start and the end points.

Why?

Since each block is 180 m long, we need to calculate the vertical and the horizontal distance, in order to calculate how farther did the travel walk between the start and the end points (displacement).

So, calculating we have:

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Actual distance between the start and the end point (displacement):

ActualDistance=\sqrt{NorthDistance+EastDistance}\\\\ActualDistance=\sqrt{NorthDistance^{2} +EastDistance^{2}}\\\\ActualDistance=\sqrt{(720m)^{2} +(540m)^{2}}\\\\ActualDistance=\sqrt{518400m^{2} +291600m^{2}}\\\\ActualDistance=\sqrt{810000m^{2}}=900m

Now, to calculate how much farter did the traveler walk, we need to use the following equation:

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Have a nice day!

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To read more about the conservation of energy, please go to brainly.com/question/14668053

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