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2 years ago

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A baseball of mass m = 0.49 kg is dropped from a height h1 = 2.25 m. It bounces from the concrete below and returns to a final h

eight of h2 = 1.38 m. Neglect air resistance. Randomized Variables m = 0.49 kg h1 = 2.25 m h2 = 1.38 m show answer No Attempt 33% Part (a) Select an expression for the impulse I that the baseball experiences when it bounces off the concrete.

1 answer:

Brilliant_brown [7]2 years ago

6 0

Answer:

Explanation:

Impulse = change in momentum

mv - mu , v and u are final and initial velocity during impact at surface

For downward motion of baseball

v² = u² + 2gh₁

= 2 x 9.8 x 2.25

v = 6.64 m / s

It becomes initial velocity during impact .

For body going upwards

v² = u² - 2gh₂

u² = 2 x 9.8 x 1.38

u = 5.2 m / s

This becomes final velocity after impact

change in momentum

m ( final velocity - initial velocity )

.49 ( 5.2 - 6.64 )

= .7056 N.s.

Impulse by floor in upward direction

= .7056 N.s

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2 years ago

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A charge of 8.4 × 10–4 C moves at an angle of 35° to a magnetic field that has a field strength of 6.7 × 10–3 T. If the magnetic

larisa86 [58]

Answer:

The charge is moving with the velocity of $1.1\times10^{4}\ m/s$ .

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We need to calculate the velocity.

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The magnetic force is defined as:

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1 year ago

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<span>Use the kinematic equation vf^2 = vi^2 + 2ad where;
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2 years ago

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