A book is sitting on a desk. What best describes the normal force acting on the book?

During a tennis match, a player serves the ball at 27.4 m/s, with the center of the ball leaving the racquet horizontally 2.34 m

Maurinko [17]

a. The ball's horizontal and vertical positions at time $t$ are given by

$x=\left(27.4\,\dfrac{\rm m}{\rm s}\right)t$

$y=2.34\,\mathrm m-\dfrac g2t^2$

The ball reaches the net when $x=12.0\,\rm m$ :

$12.0\,\mathrm m=\left(27.4\,\dfrac{\rm m}{\rm s}\right)t\implies t=0.438\,\rm s$

At this time, the ball is at an altitude of

$2.34\,\mathrm m-\dfrac g2\left(0.438\,\mathrm s\right)^2=1.40\,\mathrm m$

which is 1.40 m - 0.900 m = 0.500 m above the net.

b. The change in angle gives the ball the new position functions

$x=\left(27.4\,\dfrac{\rm m}{\rm s}\right)\cos(-5.00^\circ)t$

$y=2.34\,\mathrm m+\left(27.4\,\dfrac{\rm m}{\rm s}\right)\sin(-5.00^\circ)t-\dfrac g2t^2$

The ball reaches the net at time $t$ such that

$\left(27.4\,\dfrac{\rm m}{\rm s}\right)\cos(-5.00^\circ)t=12.0\,\mathrm m\implies t=0.440\,\mathrm s$

at which point the ball's vertical position would be

$2.34\,\mathrm m+\left(27.4\,\dfrac{\rm m}{\rm s}\right)\sin(-5.00^\circ)\left(0.440\,\mathrm s\right)-\dfrac g2\left(0.440\,\mathrm s\right)^2=0.343\,\mathrm m$

so that the ball does not clear the net with 0.343 m - 0.900 m = -0.557 m.

5 0

2 years ago

Water pumps use electrical energy to create mechanical energy needed to move water.

Afina-wow [57]

Answer:

n/a

Explanation:

this question is not feasible

3 0

2 years ago

In order to move a bag of dog food across a 10 meter room you apply20 Newton’s of force how much work was done?

lilavasa [31]

The work done is calculated by multiplying the Force by the distance. So, 10x20 = 200 joules.
I hope this is the answer you are looking for, if not good luck on finding your answer ;D

8 0

3 years ago

The purpose of the fraud fighter/ black light machine is to:

Aleks [24]

The purpose of the fraud fighter or also known as black light machine is that it has the ability to check counterfeited bills. It is designed to be a detector with the counterfeited bills, plus, it is a way of verification. It is composed of a UV light, where in, making it have the ability to detect the counterfeited bills which is its task to do.

3 0

2 years ago

What happend to the egg in the fresh water glass?

Molodets [167]

Answer:

Nothing in the fresh water

The egg will be salty in salt water

Mark as brainlist

8 0

2 years ago

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