Answer:
15.32°
Explanation:
We have given the wavelength 
Diffraction grating is 1460 lines per cm
So
(as 1 m=100 cm )
For maximum diffraction
here m is order of diffraction
So 


Answer:
1.5m
Explanation:
Velocity=1500m/s
Frequency=1000hz
Wavelength =velocity ➗ frequency
wavelength =1500 ➗ 1000
Wavelength=1.5m
Answer:
Weight
Explanation:
The spring balance is used to measure weight of an object.
Answer:
1750 Joules.
Explanation:
Work done = force * distance
= 7 * 250
= 1750 Joules.