<span>0.52%
First, let's convert that speed into m/s.
150 km/h * 1000 m/km / 3600 s/h = 41.667 m/s
Now let's see how much time gravity has to work on the ball. Divide the distance by the speed.
18 m / 41.667 m/s = 0.431996544 s
Now multiply that time by the gravitational acceleration to see what the vertical component to the ball's speed that gravity adds.
0.431996544 s * 9.8 m/s^2 = 4.233566131 m/s
Use the pythagorean theorem to get the new velocity of the ball.
sqrt(41.667^2 + 4.234^2) = 41.882 m/s
Finally, let's see what the difference is
(41.882 - 41.667)/41.667 = 0.005159959 = 0.5159959%
Rounding to 2 figures, gives 0.52%</span>
A simple machine can make work easier by reduce the amount of energy needed to perform a task, therefore, B. <span>it magnifies the potential energy so that the kinetic energy is greater</span> is the correct answer.
3, protons are positive and there are 3 positive atoms visible
The applicable relationship is N1/N2 = V1/V2, meaning the ratio of primary voltage to secondary voltage is equal to the ratio of primary turns to secondary turns.
Here N1 = 1000, V1 = 250, V2 = 400V and N2 = TBD.
Rewriting the above relationship, N2 = N1 V2/V1 = 1000 x 400/250 = 1600 turns.
