Answer:
90x20=1800
Explanation:
just multiply 10 & 9 and then mutiply 90x20 or 20x90
The number of electrons in a neutral atom is equal to the number of protons. The mass number of the atom (M) is equal to the sum of the number of protons and neutrons in the nucleus. The number of neutrons is equal to the difference between the mass number of the atom (M) and the atomic number. Therefore, it is true!
Yes, C is correct. It self explains itself as we know light travels through a vacuum ( doesn't need a medium) and light is a type of electromagnetic wave.
Materials required for the experiment of limiting force borne by string:-
- String balance
- weights
- light strings
- weight hanger
- pan for spring balance
- Sand
Steps of procedure for for the experiment of limiting force borne by string:-
- First we have to tie a light string to the fixed support and then tie the other end with the weight hanger consists of weight.
- Add additional weight to the hanger again and again. And continue the same until the string is broken.
- Note down the weight (x) where the string is broken.
- Suspend spring balance to a support.
- Tie the light string at the end of the balance and at the other end suspend the pan for spring balance.
- Now place the weights (x-100 grams) in pan.
- Observe the reading in the spring balance.
- Add a small amount of sand in the pan by observing the readings.
- same is to be done till the string is broken.
Learn more about limiting force here:- brainly.com/question/11371672
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