The time for half the atoms in a radioactive substance to disintegrate
https://www.vocabulary.com/dictionary/half-life
Answer:
photoelectric effect
Explanation:
When the energy from photons is absorbed by matter, the matter can emit electrons. This process is called the photoelectric effect. The photoelectric effect is a property of light that is not explained by the theory that light is a wave.
The light will bend when in
Question
What was the initial momentum of the bullet before collision?
Answer:
10 Kg.m/s
Explanation:
Momentum is a product of velocity of an object in m/s and its mass in kgs hence numerically expressed as p=mv where p is momentum, v is velocity and m is mass. Substituting m for 0.2 kg and v for 50 m/s then p=0.2*50=10 kg.m/s
The correct answer is
Air resistance
In fact, when a ball is in free fall, there are two forces acting on it:
- its weight (force of gravity), acting downward
- the air resistance, acting upward
The effect of the weight is to accelerate the ball, because its direction is the same as the direction of motion of the ball, while the effect of the air resistance is to slow down the ball, because its direction is opposite to that of the motion.