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Mariana [72]
2 years ago
9

a ball is thrown horizontally from the roof of a building 45.0 m tall and lands 24.0 m from the base. What was the ball´s initia

l speed?
Physics
1 answer:
Sliva [168]2 years ago
4 0

ball drops 45m under g=10m/s/s

45=1/2x10xt^2 ... application of kinematic equaion from rest

90/10=t^2

t=3

24.0 m in 3 secs => 8m/s no air resistance

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(a) Find the acceleration of B.<br>(b) Find the tensions, T1 and T2, in the strings.
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Rony fills a bucket with water and whirls it in a vertical circle to demonstrate that the water will not spill from the bucket a
Romashka-Z-Leto [24]

Answer:

0 N, 3.49 m/s

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If we take the sum of the forces in the radial direction, where towards the center is positive:

∑F = ma

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W = m v² / r

mg = m v² / r

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8 0
3 years ago
A robot is exploring​ charon, the dwarf planet​ pluto's largest moon. Gravity on charon is 0.278 meters per second ​[m divided b
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V = \frac{4}{3}\pi *(\frac{0.06}{2})^3

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Now it is given that it's specific gravity is 10.8

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now change in potential energy is given as

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i = current = 1.83 mA

t = time = 12 s

E = 10* 1.83 * 10^{-3} * 12

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Now efficiency is defined as the ratio of output work with given amount of energy used

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\eta = \frac{0.051}{0.22} = 0.23

so efficiency will be 23 %

5 0
2 years ago
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