Woollen cloth protects the body from cold because
A). It is a good conductor of heat
B). It is a poor conductor of heat
C). External heat rays enter into the body through the woollen cloth
D). It reflects heat
It is a poor conductor of heat
Cotton clothes are thin and do not have space in which air can be trapped. Thus, cotton clothes do not prevent heat coming out of our body. Woollen clothes keep us warm during winter because wool is a poor conductor of heat and it has air trapped in between the fibres.
1. Through which light cannot pass?
2. Negative feedback in amplifiers
3. A fuse is used in an electric circuit to -
4. Thermal electricity is generated by using which of these ?
6. If the length of a simple pendulum is halved then its period of oscillation is
8. Rain drops fall from great height. Which among the following statements is true regarding it?
9. If speed of rotation of the earth increases, the weight of the body