Question

D. Tick (✓) the most appropriate answer.

1. A thick glass tumbler cracks when boiling hot water is poured into it because :

(a) glass is a bad conductor of heat

(b) inner surface of glass expands more
than outer surface

(c) outer surface of glass expands more
than inner surface

(d) both (a) and (b).

2. A bimetallic strip of brass and iron is straight
at room temperature. When this bimetallic strip is heated it bends, such that :

(a) iron takes the outer surface of bend

(b) brass takes the outer surface of bend

(c) the bimetallic strip does not bend

(d) none of these

3. Small gaps are left between railway lines
because :

(a) we cannot have rails of very long lenght

b ) it allows for expansion of rails during summer

c)it allows for contraction of rails during summer

d) both (b) and (c)

4.Iron tyres are mounted on the wooden wheel of a Tonga. Intially the diameter of the iron tyre is:

a) slightly more than the wooden wheel

b)slightly less than the wooden wheel

c) of same diameter as wooden wheel

d)none of these

5. A bimetallic strip is used in:

a) pressure cooker
b) automatic fire alarm
c) ceiling fan
d) flash light

Helpppppp❤️❤️❤️​

Answer 1

Explanation:

B}. Option

A}. Option

I hope it may help to you