4.
II. Write whether the following statements are true or false, if the statement is false correct it.
Every object moves with a constant speed. [ ]
2. An electric bell has an electromagnet. [ ]
3.
When current is switched ‘ON in a room heater, it becomes red hot and emits heat. [ ]
Cells connected in a series form a battery. [ ]
5. Speedo meter records the distance travelled by a vehicle. [ ]
6. The distance time graph of standing vehicles is a straight line parallel to y - axis [ ]
7. MCB works on the magnetic effect of current. [ ]
8. When an electric current flows through a wire, it behaves like a magnet. [ ]
9. Periodic events are used for the measurement time. [ ]
10. The image formed in a plane mirror is behind mirror. [ ]
Answers
Explanation:
1.false
2.true
3.true
4.true
7.false
8.false
10. i didn't understood
Answer:
1)- FALSE, - The statement that every object moves with a constant speed is false. Explanation: Speed can be defined as the rate of change in distance of the body. For any body which is accelerating in a certain direction the speed of that body is changing at any interval.
2)-TRUE
3)- TRUE
4)- TRUE
5)- TRUE
6)- FALSE, - The distance-time graph gives the speed. Since vehicle is standing i.e. the vehicle is at rest. So the speed of vehicle is zero. The zero speed in distance - time graph is given by is a straight line parallel to \( x-\)axis.
7)-TRUE
8)-TRUE
9)- TRUE
10)- The image formed by a plane mirror is laterally inverted, upright, of the same size and is formed far behind the mirror as the object is in front of it.