Explanation:
From the given figure,
Mass of ball A is 4.9 kg and its initial speed is 8 m/s.
Mass of ball B is 1.9 kg and its initial speed is 14 m/s.
Mass of ball C is 0.7 kg and its initial speed is 2 m/s.
We need to find the final speed of the balls 1 s after being thrown. They all are thrown upward under the action of gravity. The equation of motion is : v = u -gt, g = 10 m/s²
For ball A,
v = 8-10(1) = = -2 m/s (downward)
For B,
v = 14-10(1) = 4 m/s (upward)
For C,
v = 2-10(1) = -8 m/s (downward)
It means the ranking is B>A>C i.e. the speed of ball B is the most and that of C is least.
All the balls are moving under the action of gravity. It would mean that the acceleration for all balls is same i.e. 10 m/s²
(2π rad/year) x (1 yr/365 days) x (1 day / 86,400 seconds)
= (2π) / (365 x 86,400) rad/sec
= 0.000 000 2 radian/sec
= 0.2 microrad/sec
You can compare the velocity of the car, 60 mph, with the velocity that a mass would acquire when falls from certain height.
First, convert 60 mph to m/s:
60 miles/h * 1.60 km/mile * 1000 m/km * 1h/3600s = 26.67 m/s
Second, calculate from what height a body in free fall reachs 26.67 m/s velocity when hits the floor.
free fall => Vf^2 = 2g*H => H = Vf^2 / (2g)
H = (26.67m/s)^2 / (2*9.8 m/s) = 36.2 m
If you consider that the height between the floors of a building is approximately 3.6 m, you get 36.2 m / 3.6 m/floor = 10 floors.
Then, you conclude that the force of impact is the same as driving you vehicle off a 10 story building.
Hello,
The answer is option B KE=1/2mv^2.
Reason:
In order to calculate the kinetic energy of a object you need to use option B which is the correct formula to find the kinetic energy.
If you need anymore help feel free to ask me!
Hope this helps!
~Nonportrit
According to the second law of thermodynamics,
the answer is
<span>4. The entropy of the universe is increasing. </span>
