Answer:
a) 0.138J
b) 3.58m/S
c) (1.52J)(I)
Explanation:
a) to find the increase in the translational kinetic energy you can use the relation

where Wp is the work done by the person and Wg is the work done by the gravitational force
By replacing Wp=Fh1 and Wg=mgh2, being h1 the distance of the motion of the hand and h2 the distance of the yo-yo, m is the mass of the yo-yo, then you obtain:

the change in the translational kinetic energy is 0.138J
b) the new speed of the yo-yo is obtained by using the previous result and the formula for the kinetic energy of an object:

where vf is the final speed, vo is the initial speed. By doing vf the subject of the formula and replacing you get:

the new speed is 3.58m/s
c) in this case what you can compute is the quotient between the initial rotational energy and the final rotational energy

hence, the change in Er is about 1.52J times the initial rotational energy
Answer:
So an object with mass is attracted to another object with mass, and the gravitational force is directly proportional to the masses of the two objects, and inversely proportional to the <em>square</em> of the distance between the two objects.
If distance were to increase, than the gravitational force would decrease. If mass were to increase, so would the gravitational force.
Explanation:
Answer:
38.8 m
Explanation:
h = -(21 + 1.75) = - 22.75 m
g = - 9.8 m /s^2
Ux = 14.004 m/s
Uy = + 5.376 m/s
Let the ball hits the ground in time t and at a distance d from the base of hill.
Use second equation of motion
h = Uyt + 0.5 at^2
- 22.75 = 5.376 t - 0.5 x 9.8 t^2
4.9 t^2 - 5.376 t - 22.75 = 0

By solving
t = 2.77 second
So, horizontal distance
d = Ux t
d = 14.004 x 2.77 = 38.8 m
Answer:
0 N/C
Explanation:
Parameters given:




The distance between
and
is

Electric field is given as

r = 15/2 = 7.5cm = 0.075m
The electric field at their midpoint due to
is:

= 
The electric field at the midpoint due to
is:

= 
The net electric field will be:
E =
+ 
E =
+ 
E = 0 N/C