Answer:
Minimum diameter=1.714
Explanation:
Angular magnification=fob/fey=42
fob=40*fey
Hence minimum diameter=diameter of objective/angular magnification
minimum diameter=72/42=1.714
Here, Initial momentum = mu = 5*1 = 5 Kg m/s
Final momentum = mv = 5*2 = 10 Kg m/s
So, Momentum has been increased from 5 Kg m/s to 10 Kg m/s. Hence, Your Final answer is option B
Hope this helps!
Answer:
a) 
b) This value of specific heat is close to the specific heat of ice at -40° C and the specific heat of peat (a variety of coal).
c) The material is peat, possibly.
d) The material cannot be ice because ice doesn't exists at a temperature of 100°C.
Explanation:
Given:
- mass of aluminium,

- mass of water,

- initial temperature of the system,

- mass of copper block,

- temperature of copper block,

- mass of the other block,

- temperature of the other block,

- final equilibrium temperature,

We have,
specific heat of aluminium, 
specific heat of copper, 
specific heat of water, 
Using the heat energy conservation equation.
The heat absorbed by the system of the calorie-meter to reach the final temperature.



The heat released by the blocks when dipped into water:

where
specific heat of the unknown material
For the conservation of energy : 
so,


b)
This value of specific heat is close to the specific heat of ice at -40° C and the specific heat of peat (a variety of coal).
c)
The material is peat, possibly.
d)
The material cannot be ice because ice doesn't exists at a temperature of 100°C.
Answer: 75V
Explanation:
Given that,
total resistance (Rtotal) = 150Ω
Current (I) = 0.5A
Change in electric potential (V) = ?
Recall that potential difference is the product of amount of current and the amount of resistance in the circuit. And its unit is volts.
So, apply the formula V = I x Rtotal
V = 0.5A x 150Ω
V = 75V
Thus, the change in electric potential across the circuit is 75 Volts
Answer:

Explanation:
The temperature in stratosphere is generally about 270 K
molecular weight of an ozone molecule = 48 gm/mole
now formula for most probable velocity

plugging the values we get

