Question

Physics Review Questions. Please help quickly!!
Will give medal to best answer!
A pitcher exerts 100.0 N of force on a ball with a velocity of 45 m/s. What is the pitcher's power?

A 50.0 kg sailor climbs a 28.3 m rope ladder at an angle of 45 degrees with the mast. How much work did he do?

An inclined plane is 5.00 m long and 2.00 m high. What is the ideal mechanical advantage of this machine?

A sailboat moves north for a distance of 10.00 km when blown by a wind 30 degrees east of south with a force of 5.00 x 10^4 N. How much work was done by the wind?

Answer 1

@petiteme

Answer 2

@sheelo73mughal

Answer 3

For the first question I think it might be 2.2 W and for the second I think it might be 1.00 x 10^3 J?

Answer 4

For the first one...Power = force x velocity :D

Answer 5

so 4,500?

Answer 6

@petiteme ?

Answer 7

Good job! ^_^

Answer 8

great! now for the second question

Answer 9

would it be 50.0 x 28.3 x cos45?

Answer 10

What formula did you use?

Answer 11

You used... Work = Force x Displacement x Cosine(theta)

Answer 12

force x distance x cos theta I think

Answer 13

But 50.0 is just the mass right?

Answer 14

yes

Answer 15

force = mass x acceleration?

Answer 16

And Force = mass x acceleration

Answer 17

Yes! Good job :D

Answer 18

cool! So, it would be 50.0 x 9.8m/s?

Answer 19

Yes :)

Answer 20

so 490 x 28.3 x cos45?

Answer 21

Yes :)

Answer 22

9805?

Answer 23

@petiteme

Answer 24

Lemme get my calculator :D

Answer 25

Good job! Don't forget the significant figures. It might be needed. Lol ^_^

Answer 26

thanks! ok next question

Answer 27

would it be 5.00/2.00?

Answer 28

Inclined plane formula is length/height

Answer 29

So yes ^_^

Answer 30

cool so that would be 2.5?

Answer 31

Good job ^_^ 2.50 to be exact. Hehehe

Answer 32

haha! :) cool

Answer 33

You got the last question?

Answer 34

would I use the work formula?

Answer 35

@petiteme

Answer 36

Yes :)

Answer 37

Tell me what you got ^_^

Answer 38

433012.70?

Answer 39

Yep :D But significant figures again. Lol. Hey, don't forget the units ^_^ Good job! :D

Answer 40

oh ok lol