A projectile is any object that is thrown, dropped or otherwise laughed into the air.
1) If it is dropped - it's motion is caused by just gravitation force
2) if it is thrown - it's motion is caused by gravitation force + force you applied to though it upwards
Answer:
<em>The correct choice is D. Its gravitational potential energy must increase</em>
Explanation:
<u>Conservation of Mechanical Energy</u>
The total amount of mechanical energy, in a closed system in the absence of dissipative forces like friction or air resistance, remains constant.
This means that energy cannot disappear or appear and that potential energy can become kinetic energy or vice versa.
In a closed system like a pendulum, two types of energies are considered: Gravitational potential (U) and kinetic (K). Thus, the sum of both energies must remain constant in time.
Suppose the pendulum is at a state where U=150 J, and K=350 J. The total mechanical energy is:
M = 150 J + 350 J = 500 J
If the kinetic energy decreases to a new value, say K = 200 J, then the gravitational potential must increase to compensate for this new condition, that is: U = 300 J
The correct choice is D. Its gravitational potential energy must increase
The appropriate hypothesis test for this question is the two proportions test. As the name implies, it is often used to compare existing percentages between two groups. The raw data behind the percentages must be available as the sample size becomes crucially important in determining the test statistics.
The test statistic of the two-proportion test is the Z value. When the sample becomes very large, the Z value is governed under a normal function and is commonly known as the standardized Z value
Surface waves fits that description.
Answer:
both are 45√2N
Explanation:
90 sin45°=90 cos45°=45√2N