3 is false 2 is true and the rest true
Sometimes if you have the word per, you need to multiply. In this problem, they are asking you to find the amount of meters a snail can travel per minute.They are giving you the amount of minutes, so in this case you multiply 15 times 0.30. The answer is 4.5 meters.
Answer:
f = 1 m
Explanation:
The magnification of the lens is given by the formula:

where,
M = Magnification = 4
q = image distance = 5 m
p = object distance = ?
Therefore,

Now using thin lens formula:

<u>f = 1 m</u>
Answer:
e. 1.2 x 10²³
Explanation:
According to the problem, The current equation is given by:

Here time is in seconds.
Consider at t=0 s the current starts to flow due to battery and the current stops when the time t tends to infinite.
The relation between current and number of charge carriers is:

Here the limits of integration is from 0 to infinite. So,


q = 1.90 x 10⁴ C
Consider N be the total number of charge carriers. So,
q = N e
Here e is electronic charge and its value is 1.69 x 10⁻¹⁹ C.
N = q/e
Substitute the suitable values in the above equation.

N = 1.2 x 10²³