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3 years ago

50 points!!! Kinetics

Physics

2 answers:

enyata [817]3 years ago

7 0

Answer:

h = 98m

Explanation:

The ball follows a projectile motion.

It it's at the same height at t = 2 and t =10,

It was at a max height at:

t = (2+10)/2

= 12/2

= 6s

Conventional: upwards positive

s = ut + ½at²

s = ut + ½(-9.8)t²

s = ut - 4.9t²

s is equal at t = 2 and t = 10

2u - 4.9(2)² = 10u - 4.9(10)²

2u - 19.6 = 10u - 490

8u = 470.4

u = 58.8

at t = 2

s = 58.8(2) - 4.9(2)²

s = 98 m

iris [78.8K]3 years ago

3 0

Answer:

98 m √

Explanation:

How about s = Vo * t + ½at² ?

s = h = Vo * 2s - 4.9m/s² * (2s)² = 2Vo - 19.6

and

h = Vo * 10s - 4.9m/s² * (10s)² = 10Vo - 490

Subtract 2nd from first:

0 = -8Vo + 470.4

Vo = 58.8 m/s

h = 58.8m/s * 2s - 4.9m/s² * (2s)² = 98 m

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$\Delta p\geq m\Delta v\geq 2.78\times 10^{-35}\\\Rightarrow \Delta v\geq \dfrac{2.78\times 10^{-35}}{m}\\\Rightarrow \Delta v\geq \dfrac{2.78\times 10^{-35}}{0.045}\\\Rightarrow \Delta v\geq 6.178\times 10^{-34}\ \text{m/s}$

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Suppose a child drives a bumper car head on into the side rail, which exerts a force of 3900 N on the car for 0.55 s. Use the in

-Dominant- [34]

Answer:

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The final velocity is -8.34 m/s or 8.34 m/s in he opposite direction.

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The final momentum = mv2

where v2 is the final momentum of the car.

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2145 = 560.5 - 190v2

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1584.5 = -190v2

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