Answer:74.33 feet per sec
Explanation:
Given
Police car is 50 feet side of road
Red car is 140 feet up the road
Distance between them is decreasing at the rate of 70 feet per sec
From figure


z=148.66 feet
as the red car is moving
therefore its velocity magnitude is given by





gravitational potential is directly proportional to the height of the object relative to a reference line and is given as
PE = mgh
where m = mass of object , g = acceleration due to
gravity and h = height of the object above the reference line .
as the skydiver falls , its height above the ground decrease and hence the gravitational potential energy of the skydiver decrease.
as per conservation of energy , total energy of the skydiver must remain constant all the time . hence the decrease in potential energy appears as increase in kinetic energy by same amount to keep the total energy constant
KE + PE = Total energy
so as the skydiver falls , it gains speed and hence the kinetic energy of skydiver increase since kinetic energy is directly proportional to the square of the speed.
when the parachute opens, the skydiver experience force in upward which tries to balance the weight of the skydiver. hence the speed of the skydiver decrease until upward force becomes equal to the downward force. hence the kinetic energy decrease just after the parachute opens
Force = mass x acceleration
15 = mass x 4
Mass = 15/4
Mass = 3.75 Kg
Answer:
The smallest diameter is 
Explanation:
From the question we are told that
The resolution of the telescope is 
The wavelength is 
From the question we are told that

So 
Therefore


Now 
So 
=> 

The smallest diameter is mathematically represented as

substituting values

