The examples of levers are seesaw, door and corkscrew
Answer: Option A, B, and C
<u>Explanation:</u>
A simple machine which is capable of rotating or moving with respect to a fixed point at the center of mass is termed as lever. Lever is made up of a rigid rod which acts as the beam or the object on which the effort can be applied based on the load and a fixed hinge like thing named as fulcrum or the center of mass.
The fulcrum will be fixed and the beam will be rotating or moving with the support of fulcrum at the center for given load or effort. So among the given options, ramp is not falling under the categories of lever as door also have a fulcrum. But the ramp is only an inclined plane without fulcrum. But the Seesaw, door and the corkscrew has both fulcrum and beam which confirms them falling in the category of lever.
Answer:
The 60 kg skater is traveling at 2.63 m/s in the opposite direction from the 45 kg skater.
Explanation:
The velocity of the 60 kg skater can be found by conservation of linear momentum:

(1)
Where:
: is the mass of the first skater = 45 kg
: is the mass of the second skater = 60 kg
: is the initial speed of the first skater = 0 (he is standing still)
: is the initial speed of the second skater = 0 (he is standing still)
: is the final speed of the first skater = 3.5 m/s
: is the final speed of the second skater =?
By replacing the above values into equation (1) and solving for
we have:

The minus sign is because the 60 kg skater is moving in the opposite direction from the other skater.
Therefore, the 60 kg skater is traveling at 2.63 m/s in the opposite direction from the 45 kg skater.
I hope it helps you!
6b: impulse is change in momentum. Change in momentum p=m[v(final)-v(initial). Final velocity is zero and initial velocity is the one you calculated before impact: -15.7 since it’s going down. Now plug in numbers and you get 78.5 in the upward direction.
6c: change in momentum p=Ft. we already calculated change in momentum. So plug it into equation and solve for t. 78.5/655= 0.119 s
Apply the same idea for question 7. Hope this helped
Answer:
60mph=26.8224meters per second
Explanation: