Answer:
Positive.
Explanation:
As a consequence of the photoelectric effect, electrons that will get hit by sufficiently energetic photons will abandon the metal surfaces exposed to bright sunlight. This decreases the negative charge of the surface, thus causing it to develop a positive net charge.
Answer:B
Explanation: I think this is the answer
No, he did not perform any work. Work is when you’re using energy which results in a force. Even though he was tired and sweaty, he did not move the boulder. So therefore he did not perform any work.
Answer: Option <em>a.</em>
Explanation:
Kepler's 2nd law of planetary motion states:
<em>A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.</em>
It tells us that it doesn't matter how far Earth is from the Sun, at equal times, the area swept out by Earth's orbit it's always the same independently from the position in the orbit.
In physics we refer to how heavy the object is as the mass.
Fg = mass x acceleration due to gravity
Force is directly proportional to mass, thus if force of gravity increases mass also increases.