Answer:
4334.4 J
Explanation:
Work done equals to kinetic energy change
KE=½mv²
Change in KE is given by
∆KE=½m(v²-u²)
Where m is mass of water-skier, KE is kinetic energy, ∆KE is the change in kinetic energy, v is final velocity and u is initial velocity.
Substituting 72 kg for m, 12.1 m/s for v and 5.10 m/s for u then
∆KE=½*72(12.1²-5.10²)=4334.4J
Therefore, the work done by the net external force acting on the skier is equal to 4334.4 J
Answer:
orbitals
Explanation:
The region where an electron is most likely to be is called an orbital. Each orbital can have at most two electrons. Some orbitals, called S orbitals, are shaped like spheres, with the nucleus in the center.
Answer:
(a) Distance traveled = 75.3846 m
(b) Velocity of car at that instant will be 14 m/sec
Explanation:
We have given acceleration of the car 
Initial velocity of the cart u = 0 m/sec
(a) According to second equation of motion we know that 
So distance traveled by car 
As the truck is moving with constant speed
So distance traveled by truck 
As the truck overtakes the car
So 
So distance traveled 
(b) From second equation of motion we know that v = u+at
So v = 0+1.3×10.769 = 14 m /sec
Answer:
20,000,000 N
Explanation:
First find the acceleration:
a = Δv / Δt
a = (0 − 40 m/s) / 0.010 s
a = -4000 m/s²
Next use Newton's second law to find the force on the car:
F = ma
F = (5000 kg) (-4000 m/s²)
F = -20,000,000 N
According to Newton's third law, the force on the wall is equal and opposite the force on the car.
F = 20,000,000 N
