Answer:
160J
Explanation:
Given force = 8N and total distance = 20 meters
Workdone = force x distance
= 8 x 20
= 160J
Therefore, workdone by Riley in pulling the hoover is 160J
The chemical energy in Jay's body, to kinetic energy in the car
Answer:Racquet force is twice of Player force
Explanation:
Given
ball arrives at a speed of 
ball returned with speed of 
average Force imparted by racquet on the ball is given by

where 
time of contact of ball with racquet


When it land on the player hand its final velocity becomes zero and time of contact is same as of racquet


From 1 and 2 we get

Hence the magnitude of Force by racquet is twice the Force by player
Answer: 1 is phone 2 is sandwich, Last is picture.
Explanation: I hoped That Helped !!
Answer:
9.96x10^-20 kg-m/s
Explanation:
Momentum p is the product of mass and velocity, i.e
P = mv
Alpha particles, like helium nuclei, have a net spin of zero. Due to the mechanism of their production in standard alpha radioactive decay, alpha particles generally have a kinetic energy of about 5 MeV, and a velocity in the vicinity of 5% the speed of light.
From this we calculate the speed as
v = 5% 0f 3x10^8 m/s (speed of light)
v = 1.5x10^7 m/s
The mass of an alpha particle is approximately 6.64×10−27 kg
Therefore,
P = 1.5x10^7 x 6.64×10^−27
P = 9.96x10^-20 kg-m/s