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Kazeer
3 months ago
8

An object is released from rest near and above Earth’s surface from a distance of 10m. After applying the appropriate kinematic

equation, a student predicts that it will take 1.43s for the object to reach the ground with a speed of 14.3m/s . After performing the experiment, it is found that the object reaches the ground after a time of 3.2s. How should the student determine the actual speed of the object when it reaches the ground? Assume that the acceleration of the object is constant as it falls.
Physics
1 answer:
serg [3.5K]3 months ago
4 0

Answer:

v_y = 12.54 m/s

Explanation:

Given values:

- Initial vertical height y_o = 10 m

- Initial velocity v_y,o = 0 m/s

- The object's acceleration in the air = a_y

- The actual time taken to reach the ground t = 3.2 s

Find:

- How to calculate the object's speed when it arrives at the ground?

Solution:

- Apply kinematic equations to find the actual acceleration of the ball when it reaches the ground:

y = y_o + v_y,o*t + 0.5*a_y*t^2

0 = 10 + 0 + 0.5*a_y*(3.2)^2

a_y = - 20 / (3.2)^2 = 1.953125 m/s^2

- Use the total energy conservation principle of the system:

E_p - W_f = E_k

Where, E_p = m*g*y_o

W_f = m*a_y*(y_i - y_f)..... Reflecting air resistance

E_k = 0.5*m*v_y^2

Thus, m*g*y_o - m*a_y*(y_i - y_f) = 0.5*m*v_y^2

g*(10) - (1.953125)*(10) = 0.5*v_y^2

v_y = sqrt(157.1375)

v_y = 12.54 m/s

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The formula for range is:

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Answer:

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Stone 1

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Released shortly thereafter, let's assume a delay of one second, we can utilize the same timing mechanism

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We can now calculate the separation distance between the two stones, which is applicable for t> = to

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The use of air bags in cars reduces the force of impact by a factor of 110.(The resulting force is only as great.) What can be s
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Answer:

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