Answer:
34.3 m/s
Explanation:
Newton's Second Law states that the resultant of the forces acting on the car is equal to the product between the mass of the car, m, and the centripetal acceleration
(because the car is moving of circular motion). So at the top of the hill the equation of the forces is:

where
(mg) is the weight of the car (downward), with m being the car's mass and g=9.8 m/s^2 is the acceleration due to gravity
R is the normal reaction exerted by the road on the car (upward, so with negative sign)
v is the speed of the car
r = 0.120 km = 120 m is the radius of the curve
The problem is asking for the speed that the car would have when it tires just barely lose contact with the road: this means requiring that the normal reaction is zero, R=0. Substituting into the equation and solving for v, we find:

Answer: 7,000 ohms
Explanation:
From the equation of ohms law V= IR
V=21 volt
I = 3 MA = 3.0×10^-3 A
So by evaluating, we have.
V= IR
21= 3.0×10^-3 × R
Then R = 21/3.0×10^-3
R= 7,000 ohms//.
Answer:
Average power output of athlete = 11025 Watts
Explanation:
Work done is defined as the product of force applied and the displacement perpendicular to the force.
Work = 
Power is defined as work done per unit time.
Power = 
Here the person lifts 900 kg.
Height = 2.5 m
Time interval = 2 seconds
Force = 
= 
= 8820 N
Work done = 
= 
= 22050 J
Power = 
= 11025 Watt