Question

An object is dropped from a height of 25 meters. At what velocity will it hit the ground?
A. 7.0 meters/second B. 11 meters/second C. 22 meters/second D. 49 meters/second E. 70 meters/second

Answer 1

use this equation..v^2=u^2+2gh

Answer 2

An engine moves a motorboat through water at a constant velocity of 22 meters/second. If the force exerted by the motor on the boat is 5.75 × 103 newtons, what is the power of the motor?
A. 7.9 × 104 watts B. 1.3 × 105 watts C. 2.5 × 105 watts D. 3.7 × 105 watts E. 5.0 × 105 watts

Answer 3

power P=F*v

Answer 4

A skateboarder with a mass of 45 kilograms is riding on a skateboard with a mass of 2.5 kilograms. What should be the velocity of the skateboarder if she has to attain a momentum of 264 kilogram meters/second?
A. 5.5 meters/second B. 55.5 meters/second C. 1.2 × 102 meters/second D. 1.2 × 103 meters/second E. 1.2 × 104 meters/second

Answer 5

do you know the answer?

Answer 6

total mass is 45+2.5=47.5 kg
m*v=264
find v

Answer 7

A 55 newton force applied on an object moves the object 10 meters in the same direction as the force. What is the value of work done on the object?

A. 0 joules
B. 5.5 joules
C. -5.5 joules
D. 5.5 × 102 joules
E. -5.5 × 102 joules

Answer 8

W=F*d

Answer 9

b or d? :O cause I get 550 but theres nothing close to that

Answer 10

550=5.5*10^2

Answer 11

nvm found it(:

Answer 12

An object of mass weighing 5.24 kilograms is raised to a height of 1.63 meters. What is the potential energy of the object at that height? Note that acceleration due to gravity is 9.8 meters/second2?

A.
65 joules
B.
84 joules
C.
91 joules
D.
1.0 × 102 joules
E.
1.5 × 102 joules

Answer 13

E=mgh

Answer 14

you make it seem so easyyyy (:

Answer 15

The landing of a spacecraft is cushioned with the help of airbags. During its landing on Mars, the velocity of downward fall is 16 meters/second. Immediately after the impact, the velocity is reduced to 1.2 meters/second. If the spacecraft has a mass of 11.5 × 104 kilograms, what is your estimate for the impulse if the time of impact is 0.8 seconds?

A.
7.5 × 105 kilogram meters/second
B.
9.0 × 106 kilogram meters/second
C.
9.4 × 104 kilogram meters/second
D.
2.1 × 106 kilogram meters/second
E.
1.0 × 103 kilogram meters/second

Answer 16

tell me what is impulse..?

Answer 17

it is the integral of a force with respect to time, which gives you the change in the momentum of the body being acted on by the force.

Answer 18

so calculate the change in momentum first...

Answer 19

idk how?/:

Answer 20

okay first find change in velocity..

Answer 21

15.8?

Answer 22

well done...now find change in momentum..

Answer 23

how do you find that

Answer 24

mass*change in velocity..

Answer 25

Haha, @souvik, you deserve like 10 medals!

Answer 26

haha..@theEric

Answer 27

yes he does more than 10 medals!!!!!!! :)