Answer:
2.1 s
Explanation:
The motion of the ball is a projectile motion. We know that the horizontal range of the ball is

And that the initial speed of the ball is

at an angle of

So, the horizontal speed of the ball (which is constant during the entire motion) is

And since the horizontal range is 50 m, the time taken for the ball to cover this distance was

which is the time the ball spent in air.
Using algebra to solve for the the cost of the glass lenses gives the value for cost of glass lenses to be 4.
<h3>What is the cost of the glass lenses?</h3>
The cost of the glass lenses is calculated as follows:
Let cost of glass be y
Cost of plastic lenses = 4y
Cost of eye exam and frames be z.
z + y = 30 (i)
z + 4y = 42 (ii)
(ii) - (i)
3y = 12
y = 4
Inconclusion, the cost of the glass lenses is 4.
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Answer:
20 m/s
Explanation:
speed is distance in a particular time
Answer:

Explanation:
Given that:
- moment of inertia of tucked body,

- rotational speed of the body,

- i.e.

- moment of inertia of the straightened body,

<u>Now using the law of conservation of angular momentum:</u>
angular momentum of tucked body=angular momentum of straight body



Answer:
Electron emitted by nucleus.