Answer:
The change in potential energy of the mass as it goes up the incline is 0.343 joules.
Explanation:
We must remember in this case that change in the potential energy is entirely represented by the change in the gravitational potential energy. From Work-Energy Theorem and definition of work we get that:
Where:
- Gravitational potential energy, measured in Joules.
- Mass, measured in kilograms.
- Gravitational acceleration, measured in meters per square second.
- Change in vertical height, measured in meters.
This work is the energy needed to counteract effects of gravity at given vertical displacement.
If we know that 
, 
and 
, the change in the potential energy of the mass as it goes up the incline is:
The change in potential energy of the mass as it goes up the incline is 0.343 joules.
Answer:
Explanation:
Force between two charges is given by the following expression
F = 
Q₁ and Q₂ are two charges and d is distance between two.
.1 =
If Q₁ becomes three times , force will become 3 times . Hence force becomes .3 N in the first case.
Force F = .3 N
If charge becomes one fourth , force also becomes one fourth .
F= 
= .025 N.
Answer:
a steady level climb until he gets to his constant speed
Explanation:
a steady level climb until he gets to his constant speed
42) The sailboat travels east with velocity
, while the current moves south with speed
. Since the two velocities are perpendicular to each other, he resultant velocity will be given by the Pytagorean theorem:
and the direction is in between the two original directions, therefore south-east. So, the correct answer is
D) 42 mph southeast
43) Since the light moves by uniform motion, we can calculate the distance corresponding to one light year by using the basic relationship between velocity, space and time. In fact, we know the velocity:
and the time is one year, corresponding to:
therefore, the distance corresponding to one light year is:
Therefore, the correct answer is D.
44) For the purpose of the problem, we can assume that the light travels instantaneously from the flash to us (because the distances involved are very small), so the time between the flash and the thunder corresponds to the time it took for the sound to travel to us.
The speed of sound is
And since the time between the flash and the thunder is t=3 s, the distance is
Therefore, the correct answer is A) 3/5 mile.
