Answer:
The difference in the length of the bridge is 0.42 m.
Explanation:
Given that,
Length = 1000 m
Winter temperature = 0°C
Summer temperature = 40°C
Coefficient of thermal expansion 
We need to calculate the difference in the length of the bridge
Using formula of the difference in the length

Where,
= temperature difference
=Coefficient of thermal expansion
L= length
Put the value into the formula


Hence, The difference in the length of the bridge is 0.42 m.
Answer:

Explanation:
given.
magnification(m) = 400 x
focal length (f_0)= 0.6 cm
distance between eyepiece and lens (L)= 16 cm
Near point (N) = 25 cm
focal length of the eyepiece (f_e)= ?
using equation





Potential energy of spring equals K times X squared divided by 2 where X is displacement
4 times squared equals 16
choose 1st answer