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Viefleur [7K]
2 years ago
14

(b) A ball is thrown vertically upwards with

Physics
1 answer:
harina [27]2 years ago
6 0

Answer:

5 seconds

Explanation:

The vertical position of the ball will be given by the equation

df = do + vo t + 1/2 a t^2        df = final position  = 0  ( on the ground

                                              do = original position  ( 25 m )

                                               vo = original velocity (+ 20 m/s)

                                                a = - 10 m/s^2

So this becomes

0 = 25 + 20 t  - 1/2 (10)t^2      

  =  - 5 t^2 +20 t + 25             Use Quadratic Formula   a = -5    b=20  c = 25

                                                      to find the positive value of t = 5 seconds

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Explanation:

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3 years ago
When the cylinder is displaced slightly along its vertical axis it will oscillate about its equilibrium position with a frequenc
Nesterboy [21]

Answer:

w = √[g /L (½ r²/L2 + 2/3 ) ]

When the mass of the cylinder changes if its external dimensions do not change the angular velocity DOES NOT CHANGE

Explanation:

We can simulate this system as a physical pendulum, which is a pendulum with a distributed mass, in this case the angular velocity is

          w² = mg d / I

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        I = m (¼ r2 + ⅓ L2)

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let's substitute

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         w = √[g /L (½ r²/L2 + 2/3 ) ]

When the mass of the cylinder changes if its external dimensions do not change the angular velocity DOES NOT CHANGE

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4 years ago
What's the minimum number of calories to eat per day?
vovikov84 [41]
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3 0
3 years ago
A horse has a momentum of 25 kg*m/s and a velocity of 2.5 m/s. What is the horse mass?
Ne4ueva [31]
<h3>Answer:  10 kg</h3>

==================================================

Work Shown:

We have these variables

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Solving for the mass gets us...

p = m*v

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25/2.5 = m

10 = m

m = 10

The mass of the horse is 10 kg.

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4 years ago
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