Question

Jelld no. 1 to 12 MCQ (1marks)
Serial no. 13 to 20 VSA questions (1marks)
Serial no.21 to 26 SA-1 questions (2marks)
Serial no.27 to 37 SA-2 questions (3marks)
Serial no.38 to 40 LA questions (5marks)
SECTION-A (carries 1 mark each)
1. Which of the following can a force acting on an object not change?
(a) Shape (b) Mass (c) Direction of motion (d) State of rest
2. Force of 50 N is required to bring a stationary object into motion. The force of friction acting on the
object was
(a) 100 N (b) zero
(c) 50 N (d) 150 N
3. In which medium does sound travel fastest?
(a) Vacuum (b) Air (c) Steel
(d) Water
4. Among the following which cell can be seen with an unaided eye?
(a) Hen's egg
(b) Red blood cell (c) sperm cell (d) Nerve cell
5. Some plants have nitrogen-fixing bacteria in their root nodules. What are these bacteria called?
(a) Blue green algae (b) Nitrosomonas (c) Azotobacter (d) Rhizobium
6. Vaccines are made up of-
(a) Chemicals (b) Weak microorganisms (c) Viruses (d) Drugs
7. What is the main reason that many species are becoming endangered?
(a) Habitat Destruction (b) Disease (c) Natural Selection (d) Acid rain
8.
is referred to as the variety of animals, plants and microbes generally found in an area.
(a) Flora
(b) Extinct species (c) Biodiversity (d) Fauna
9. Which one is not a coal product?
a) Coal tar b) Coal gas c) Coke d) Lime
10. Which of the following material is a good conductor of electricity?
a) Coal
b) Sulphur c) Copper d) Oxygen
11. Which of the following is a liquid at room temperature?
a) lodine b) Bromine c) Copper d) Zinc
12. Wood pulp is used to make -
a) Rayon b) Plastics c) Polyester d) Jute
13. Give the mathematical expression for pressure exerted by an object.
14. Arrange the following force of friction in correct ascending order - sliding friction, static friction and
rolling friction
15. There are two sound waves A and B. A has a higher amplitude and B has a lower amplitude. Which
one will have more decibel reading?
16. Define protoplasm.
Page 1 of 3
7. What is Red Data Book?
8. Name the synthetic fibre, which is also known as artificial silk.
9. Copper cannot displace Zinc from its salt solution, why?
o. Name the process in which dead vegetation converted into coal.​

Answer 1

Answer:

doridro

Explanation:

4. The light bulb has a tungsten filament as the light emitting media. Electricity flows through a thin tungsten wire in the light bulb called the filament. The filament used in a bulb has a property called "resistance." Resistance is the amount of friction that an object will put against electricity flowing The light bulb has a tungsten filament as the light emitting media. Electricity flows through a thin tungsten wire in the light bulb called the filament. The filament used in a bulb has a property called "resistance." Resistance is the amount of friction that an object will put against electricity flowing through it. Tungsten filament are manufactured in a way that it has a lot of resistance to electricity. As a The light bulb has a tungsten filament as the light emitting media. Electricity flows through a thin tungsten wire in the light bulb called the filament. The filament used in a bulb has a property called "resistance." Resistance is the amount of friction that an object will put against electricity flowing through it. Tungsten filament are manufactured in a way that it has a lot of resistance to electricity. As a result of this resistance, the filament heats up and starts glowing, converting electrical energy to light energy. This is because of the Joule-effect, which means that resistances heat up when an electrical current runs through them. The electricity is converted into light and heat illuminating its surroundings. of this resistance, the filament heats up and starts glowing, converting electrical energy to light energy. This is because of the Joule-effect, which means that resistances heat up when an electrical current runs through them. The electricity is converted into light and heat illuminating its surroundings. it. Tungsten filament are manufactured in a way that it has a lot of resistance to electricity. As a result of this resistance, the filament heats up and starts glowing, converting electrical energy to light energy. This is because of the Joule-effect, which means that resistances heat up when an electrical current runs through them. The electricity is converted into light and heat illuminating its surroundings.