**Answer:**

**Explanation:**

We shall apply gas law formula to get the solution .

P₁ V₁ / T₁ = P₂ V₂ / T₂

P₁ = 10⁵ + 18 x 10³ x 9.8 where 10⁵ Pa is atmospheric pressure at surface

= 1.764 x 10⁵ + 10⁵

= 2.764 x 10⁵

2.764 x 10⁵ x 3 / ( 273 + 9 ) = 10⁵ x V₂ / ( 273 + 22 )

V₂ = 8.67 cm³

**Answer:**

65.14°

**Explanation:**

The formula for the calculation of critical angle is:

Where,

is the critical angle

is the refractive index of the refractive medium.

is the refractive index of the incident medium.

The light ray is travelling from glass to ethanol

Refractive medium is ethanol with refractive index = 1.361

Incident medium is glass with refractive index = 1.500

So,

Applying in the formula as:

The critical angle is = sin⁻¹ 0.9073 = 65.14°

**Answer:**

**Giv****en****:**

Input Power ()= 1000 W

Mass (m) = 100 kg

Height (h) = 10 m

Time (t) = 16 s

**To**** ****Fi****nd****:**

Efficiency of the motor

**Explanation:**

Efficiency of the motor = 62.5 %

**Answer: The half-life is the amount of time it takes for a given isotope to lose half of its radioactivity. If a radioisotope has a half-life of 14 days, half of its atoms will have decayed within 14 days. In 14 more days, half of that remaining half will decay, and so on.**