Friction is the force you get when you (for example) Rub something with another, it's a force that may generate heat and even some resistance. Another example is rubbing your hands together, they get hot, therefore friction is working, without friction you wouldn't be able to stop moving.
Answer:
4.29 millimeters
Explanation:
Bats emit ultrasound waves: in air, ultrasound waves travel at a speed of

The frequency of the waves emitted by this bat is:

Therefore we can find the wavelength of the wave emitted by the bat by using the relationship between speed, frequency and wavelength:

It is strong enough to penetrate through flesh but not bone so we can see if there are fractures or breaks in our skeleton
Explanation:
A lever is a rigid bar which moves freely about a fixed point called fulcrum....
The types of lever are :
- First class lever
- Second class lever
- Third class lever....
Explanation:
Always behave responsibly in the laboratory. Do not run around or play practical jokes. Always check the safety data of any chemicals you are going to use. Never smell, taste or touch chemicals unless instructed to do so.