Question: A student heated some sulphur in a spatula and collected the gas ‘X’. Which one among the following is correct about ‘X’?
1. X is SO2 and it turns moist litmus to red
2. X is SO3 and it turns dry litmus to blue
3. X is SO3 and it turns moist litmus to red
4. X is SO2 and it turns moist litmus to blue
Answer: 1
Question: Solutions in test tubes containing H2O and aqueous NaOH can be differentiated with the help of:
1. blue litmus
2. red litmus
3. Na2CO3
4. HCl (aqueous)
Answer: 2
Question: Glass is actually:
1. a crystalline solid.
2. an ionic solid
3. a vitrified liquid
4. an elastic solid
Answer: 3
Question: Which one among the following is the main ingredient in cement?
1. Lime stone
2. Gypsum
3. Clay
4. Ash
Answer: 2
Question: When a ray of light is going from one medium to another, its:
1. frequency remains same
2. frequency increases
3. wavelength increases
4. wavelength remains same
Answer: 1
Question: Magnets attract magnetic substances such as iron, nickel, cobalt etc. They can also repel:
1. diamagnetic substances
2. ferromagnetic substances
3. paramagnetic substances
4. non magnetic substances
Answer: 1
Question: Mass of B is four times that of A. B moves with a velocity half that of A. Then B has:
1. kinetic energy equal to that of A.
2. half the kinetic energy of A.
3. twice the kinetic energy of A.
4. kinetic energy one-fourth of A
Answer: 1
Question: A liquid rises to a certain length in a capillary tube. The tube is inclined to an angle of 45°. The length of the liquid column will:
1. decrease
2. increase
3. first decrease and than increase
4. remain unchanged
Answer: 2
Question: Which one among the following is not a source of renewable energy?
1. Fuel cell
2. Solar energy
3. Hydroelectricity
4. Wind energy
Answer: 1
Question: ‘The stars seem to be higher on the sky than they actually are’. This can be explained by:
1. diffraction of light
2. atmospheric refraction
3. total internal reflection
4. dispersion of light
Answer: 2
Question: If the electrical resistance of a typical substance suddenly drops to zero, then the substance is called:
1. semiconductor
2. super conductor
3. conductor
4. insulator
Answer: 2
Question: The surface temperature of the Sun is nearly:
1. 2000K
2. 6000 K
3. 8000 K
4. 4000 K
Answer: 2