Answer:Answer:
They are inhaled or eaten
Explanation:
Radioactivity can be defined as the process in which an unstable atomic nucleus spontaneously emits ionizing radiation and charge particles. This eventually results in the formation of an energetically stable atomic nucleus.
Examples of radioactive elements are Uranium, Polonium, Thorium, Radon, etc. The radiation emitted during this process is classified as;
1. Alpha radiation (α).
2. Beta radiation (β).
3. Gamma radiation (G).
Alpha-emitting substances, such as radon gas, can be a serious health hazard only if they are inhaled or eaten. Alpha-emitting substances compared to other radiation has very short-range particle and as such cannot penetrate the human skin or body.
Answer:
1. high frequency and high energy.
2. short wavelengths and high frequencies.
3. less energy and long wavelengths.
4. high frequencies and high energy
5. X-rays
6. infrared waves
7. radio waves.
8. Gamma Rays
9. Microwaves
10. infrared waves
6. 0N. This questions requires understanding of how friction functions. Friction is a resistive force, meaning it opposes the direction of any applied or unbalanced forces. The box in the question experiences no horizontal force, so there is no resistive force in response to it, making it 0N.
7. This question tests your understanding of static friction. Static friction only applies when an applied or unbalanced force is applied to an object which does not move. The static friction always equals the magnitude of the applied or unbalanced force component parallel to the surface which the object rests on. The question states that the crate starts to move only when the applied force exceeds 313N, so we use this value to determine the force of static friction. The additional info in the question pertaining to when the crate is moving is irrelevant when determining static friction (only relevant if determining kinetic friction). Knowing this we solve for the weight of the crate:
F = mg
F = (45)(9.8)
F = 441N = Normal Force
The weight of the crate is also equal to the Normal Force since the object rests on a horizontal surface and the applied force is horizontal as well. In this question, since the object is not moving at 313N of applied force, the magnitude of static friction equals the applied force:
Ff = μs * Fn
(313) = μs (441)
0.71 (rounded) = μs
