Explanation:
wave is a disturbance that carries energy from one particle to another particle. The speed depends on:
1. The type of medium
2. The temperature of the medium
3. The energy of the wave
4. The amplitude of the wave
Answer:
a) a = 19.0 m/s²
b) a = 2.9 m/s²
Explanation:
a) We draw the free body diagram of the box. There are 4 forces: the normal force N, the weight mg, the constant force F and the kinetic frictional force μ_kN. We can take the coordinate system which is rotated 55° from the horizontal, to ease the calculations. So, we write the equations of motion in each axis:
Substituting the expression for N in the first equation, we have:
If we plug in the given values, we have:
Since we chose the right-downward direction as positive, the positive sign in this case means that the box is accelerated downwards above the ramp.
b) In this case, the constant force F and the kinetic frictional force μ_kN point to the opposite side. In other words, we can just only change the sign of this two forces in the equations of part (a) and obtain:
Plugging in the given values:
Since we chose the right-downward direction as positive, the negative sign in this case means that the box is accelerated upwards above the ramp.
This means that the magnitude of the acceleration in this case is 2.9m/s².
Answer:
D. radiation dose
Explanation:
The amount of energy transferred to electrons by ionizing radiation is the basis of the concept of <u>Radiation dose</u>. Radiation dose, also known as absorbed radiation dose, is the amount of energy deposited in a given mass of a medium by ionizing radiation. The international system of units (SI system) for Radiation absorbed dose and effective dose in radiation measurement are "gray" (Gy) and "sievert" (Sv), respectively.
The answer is: "nothing".
In fact, it's totally random. When there is a certain amount of atoms of a radioactive element, it's not possible to predict which atom will decay first and which one will decay later. We can only predict the amount of atoms that will be left after a certain time t (if we know the half-life of the element), but we can't predict which atom will decay first.
Hi there!
Great question!
Basketballs have air inside them. A special pump is used to insert the air. That's why you can lift the basketballs off the ground easily. If it was a solid, though, you'd hardly be able to lift the ball up! Basketballs can float, too, because anything with air inside can float. If it were solid, it would sink in the water easily.
Hope this helps! :D