# The value of the coefficient of volume expansion of glycerin is $$5\times10^{-4}$$ K-1. The fractional change in the density of glycerin for a temperature increase of $$40^\circ \mathrm{C}$$ will be: 1. $$0.015$$ 2. $$0.020$$ 3. $$0.025$$ 4. $$0.010$$

Subtopic:  Thermal Expansion |
81%
From NCERT
NEET - 2015
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Steam at $$100^{\circ}\mathrm{C}$$ is injected into 20 g of $$10^{\circ}\mathrm{C}$$ water. When water acquires a temperature of $$80^{\circ}\mathrm{C}$$, the mass of water present will be: (Take specific heat of water =1 cal g-1 $$^\circ$$C-1 and latent heat of steam = 540 cal g-1)
1. 24 g
2. 31.5g
3. 42.5 g
4. 22.5 g

Subtopic:  Calorimetry |
71%
From NCERT
NEET - 2014
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The temperature of a body falls from $$50^{\circ}\mathrm{C}$$$\mathrm{}$ to $$40^{\circ}\mathrm{C}$$$\mathrm{}$ in 10 minutes. If the temperature of the surroundings is $$20^{\circ}\mathrm{C}$$$\mathrm{, t}$hen the temperature of the body after another 10 minutes will be:
1. $$36.6^{\circ}\mathrm{C}$$
2. $$33.3^{\circ}\mathrm{C}$$$\mathrm{}$
3. $$35^{\circ}\mathrm{C}$$
4. $$30^{\circ}\mathrm{C}$$$\mathrm{}$

Subtopic:  Newton's Law of Cooling |
78%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Two rods (one semi-circular and the other straight) of the same material and of the same cross-sectional area are joined as shown in the figure. Points A and B are maintained at different temperatures. The ratio of the heat transferred through a cross-section of a semi-circular rod to the heat transferred through a cross-section of a straight rod at any given point in time will be:

1. 2: $\mathrm{\pi }$

2. 1: 2

3. $\mathrm{\pi }$: 2

4. 3: 2

Subtopic:  Conduction |
66%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The plots of intensity versus wavelength for three black bodies at temperatures ${\mathrm{T}}_{1}$${\mathrm{T}}_{2}$ and ${\mathrm{T}}_{3}$ respectively are as shown. Their temperatures are such that:

 1 $$\mathrm{T}_1>\mathrm{T}_2>\mathrm{T}_3$$ 2 $$\mathrm{T}_1>\mathrm{T}_3>\mathrm{T}_2$$ 3 $$\mathrm{T}_2>\mathrm{T}_3>\mathrm{T}_1$$ 4 $$\mathrm{T}_3>\mathrm{T}_2>\mathrm{T}_1$$
Subtopic:  Wien's Displacement Law |
63%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

One kilogram of ice at $$0^\circ \mathrm{C}$$ is mixed with one kilogram of water at $$80^\circ \mathrm{C}.$$ The final temperature of the mixture will be: (Take: Specific heat of water = $$4200$$ J kg-1 K-1, latent heat of ice$$=336$$ kJ kg-1)
1. $$0^\circ \mathrm{C}$$
2. $$50^\circ \mathrm{C}$$
3. $$40^\circ \mathrm{C}$$
4. $$60^\circ \mathrm{C}$$

Subtopic:  Calorimetry |
73%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Hot coffee in a mug cools from $$90^{\circ}\mathrm{C}$$ to $$70^{\circ}\mathrm{C}$$ in 4.8 minutes. The room temperature is $$20^{\circ}\mathrm{C}$$. Applying Newton's law of cooling, the time needed to cool it further by $$10^{\circ}\mathrm{C}$$ should be nearly:

 1 4.2 minute 2 3.8 minute 3 3.2 minute 4 2.4 minute
Subtopic:  Newton's Law of Cooling |
69%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Four rods of the same material with different radii and length $\mathcal{l}$ are used to connect two heat reservoirs at different temperatures. In which of the following cases is the heat conduction fastest?

1. $r=\frac{1}{3}\mathrm{cm},$ $\mathcal{l}=\frac{1}{9}\mathrm{cm}$

2. r = 3 cm, $\mathcal{l}$ = 9 cm

3. r = 4 cm, $\mathcal{l}$ = 8 cm

4. r = 1 cm, $\mathcal{l}$ = 1 cm

Subtopic:  Conduction |
73%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Three rods made of the same material, having the same cross-sectional area but different lengths 10 cm, 20 cm and 30 cm are joined as shown. The temperature of the junction will be:-

1. $$10.8^{\circ}\mathrm{C}$$
2. $$14.6^{\circ}\mathrm{C}$$
3. $$16.4^{\circ}\mathrm{C}$$
4. $$18.2^{\circ}\mathrm{C}$$

Subtopic:  Conduction |
70%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Three rods made of the same material and having the same cross-section have been joined as shown in the figure. Each rod has the same length. The left and right ends are kept at $$0^{\circ}\mathrm{C}$$ $and$ $$90^{\circ}\mathrm{C}$$, respectively. The temperature at the junction of the three rods will be:

1. $$45^{\circ}\mathrm{C}$$
2. $$60^{\circ}\mathrm{C}$$
3. $$30^{\circ}\mathrm{C}$$
4. $$20^{\circ}\mathrm{C}$$

Subtopic:  Conduction |
84%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints