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3 years ago

3. A ball is thrown up vertically, with a velocity of 20m/s. Calculate the maximum height

Physics

1 answer:

Deffense [45]3 years ago

8 0

Explanation:

u=20m/s

v=0m/s

g= 9.8m/s^2

h=?

v^2 = u^2 -2gh

0^2 = 20^2 -2 ×9.8×h

19.6h=400

19.6h/19.6 = 400/19.6

h=20.41m

solving for time taken for the ball to reach the ground again T =the time to reach maximum height + time the Ball takes to fall to the ground .

The time t to reach maximum height = The time t to fall to the ground

T = t+t

T=2t

u=20m/s

v=0m/s

g= 9.8m/s^2

t=?

v= u-gt

0=20-9.8t

9.8t=20

9.8t/9.8 = 20/9.8

t= 2.04seconds

T=2t

T=2(2.04)

T=4.08 seconds is the time the ball takes to reach the ground again.

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(b) The current density is inversely proportional

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$J = \frac{k}{s}$ ......(1)

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substituting (1) into (2)

$I = \frac{k}{s} \int\limits\, dS$

$I = k \int\limits^a_0 \frac{1}{s} {s} \, dS$

$I = 2\pi k\int\limits\, dS$

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$J = \frac{I}{2\pi as}$

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Answer:

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Answer:

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A car travels for 5.5 h at an average speed<br> of 75 km/h. How far did it travel?<br> T TE

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$s= 75 \ km/hr \\t= 5.5 \ hr$

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3 years ago

Positive electric charge Q is distributed uniformly throughout the volume of an insulating sphere with radius R.From the express

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Answer:

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