Answer:
See attached pictures.
Explanation:
See attachments for explanation.
The quantity that has a magnitude of zero when the ball is at the highest point in its trajectory is
the vertical velocity.
In fact, the motion of the ball consists of two separate motions:
- the horizontal motion, on the x-axis, which is a uniform motion with constant velocity

, where

- the vertical motion, on the y-axis, which is a uniformly accelerated motion with constant acceleration

directed downwards, and with initial velocity

. Due to the presence of the acceleration g on the vertical direction (pointing in the opposite direction of the initial vertical velocity), the vertical velocity of the ball decreases as it goes higher, up to a point where it becomes zero and it reverses its direction: when the vertical velocity becomes zero, the ball has reached its maximum height.
The mass of one washer is 0.0049 kg.
The mass of two washers is 0.0098 kg.
The mass of three washers is 0.0147 kg.
The mass of four washers is 0.0196 kg.
There are some missing data in the text of the problem. I've found them online:
a) coefficient of friction dry steel piston - steel cilinder: 0.3
b) coefficient of friction with oil in between the surfaces: 0.03
Solution:
a) The force F applied by the person (300 N) must be at least equal to the frictional force, given by:

where

is the coefficient of friction, while N is the normal force. So we have:

since we know that F=300 N and

, we can find N, the magnitude of the normal force:

b) The problem is identical to that of the first part; however, this time the coefficienct of friction is

due to the presence of the oil. Therefore, we have:
Answer:
0.08m/s
Explanation:
Given data
M1= 69kg
v1= 2.61m/s
M2= 0.22kg
v2= 25.2m/s
Before snowball is thrown:
Total mass of skater + snowball = 69+ 0.22 = 69.22kg
Total Momentum of skater + snowball = mv = 69.22 x 2.61 = 180.7 kgm/s
After snowball is thrown:
Let's call the velocity of the skater V.
Total momentum = momentum of skater + momentum of snowball
=69.22V + (5.544)
= 69.22V + 5.544
So:
180.7 = 69.22V+5.544
180.7- 5.544= 69.22V
175.156= 69.22V
V= 175.156/69.22
V = 2.53m/s
The total momentum after catching the snowball is mV or:
(69.0 + 0.22) x V
So:
5.544= 69.22V
V= 5.544/69.22
V=0.08m/s
The velocity of the ice skater after throwing the snowball is 0.08m/s