Answer:When white light strikes an object, each individual frequency of light is transmitted, reflected, or absorbed, depending on the properties of the surface molecules. If all frequencies are absorbed by the object, then it appears black. If all frequencies are reflected, then it appears white.
Explanation:
Answer:
a. stay the same for very long
Explanation:
It is rare for any motion to stay the same for a very long time. The force applied on a body causes changes in the magnitude of motion.
- For motion to remain constant, there must not be a net force acting on the body
- All the forces on the body must be balanced.
- This is very hard to come by.
- Motion changes very frequently.
Answer:
Part a)

Part b)

Explanation:
Part a)
Level of sound = 75 dB
now we know that

here we know that

now we have


Part b)
Intensity of sound wave is given as

here we know that

so we have


now we know



now we have


Answer:
1000 Joules per second.
Explanation:
To lift that much grass 5 meters higher than it was before the tractor did work that is the product of the (force needed to overdo gravity) and (displacement):

Power is work over the amount of time:

Answer:
Explanation:
Stress is the force applied to a rock and may cause deformation. The three main types of stress are typical of the three types of plate boundaries: compression at convergent boundaries, tension at divergent boundaries, and shear at transform boundaries.