Answer:
Option D - 0.2 s
Explanation:
We are given;
Initial velocity; u = 7 m/s
Height of table; h = 1.8m
Now,since we want to find the time the car spent in the air, we will simply use one of Newton's equation of motion.
Thus;
h = ut + ½gt²
Plugging in the relevant values, we have;
1.8 = 7t + ½(9.8)t²
4.9t² + 7t - 1.8 = 0
Using quadratic formula to find the roots of the equation gives us;
t = -1.65 or 0.22
We can't have negative t value, thus we will pick the positive one.
So, t = 0.22 s
This is approximately 0.2 s
Multiply the masses by the respective distances:
(12 kg) (2 m) = 24 J
(25 kg) (1 m) = 25 J
so the heavier bag takes more work to lift, and (b) is the answer.
(d) is technically correct if the sacks are carrying different contents whose masses are not equal, but since we don't know what's inside each sack, assume 12 kg and 25 kg are the masses of each sack *and* their contents.
Answer:
The terrestrial planets are closer to the sun.
Explanation:
Yes. Kinetic energy is a form of mechanical energy and friction will turn that kinetic energy into heat.
