Imagine you were able to throw a ball in a frictionless environment
such as outer space. Once you let go of the ball, it will travel forever
in a straight line, and at a constant speed. (At least until it bumps into
something.)
A car accelerates down the road. The reaction to the tires pushing
on the road is the road pushing on the tires.
Answer:Energy is absorbed in exact amounts that correspond to differences in energy levels.
Explanation:
According to Bohr's theory, an electron moves from a lower to a higher energy level when it absorbed photon of a given energy. The energy of the photon absorbed must be equal to the energy difference between the higher and lower energy level. Thus energy is absorbed only in discreet amounts that correspond to differences in energy levels. Absorption of energy in discreet amounts is what is meant by the term 'quantization'.
Answer:
B. 1 m/s
Explanation:
Metric unit conversions:
0.3 km = 300m
5 minutes = 5*60 = 300 seconds
So if a seal can reach a depth of 300m in a time of 300 seconds, its diving speed is the distance divided by time duration
v = s/t = 300/300 = 1m/s
So B is the correct answer
Answer:
8 Hz, 48 Hz
Explanation:
The standing waves on a string (or inside a pipe, for instance) have different modes of vibrations, depending on how many segments of the string are vibrating.
The fundamental frequency of a standing wave is the frequency of the fundamental mode of vibration; then, the higher modes of vibration are called harmonics. The frequency of the n-th harmonic is given by
where
is the fundamental frequency
In this problem, we know that the wave's third harmonic has a frequency of
This means this is the frequency for n = 3. Therefore, we can find the fundamental frequency as:
Now we can also find the frequency of the 6-th harmonic using n = 6:
