Velocity = fλ
where f is frequency in Hz, and λ is wavelength in meters.
2.04 * 10⁸ m/s = 5.09 * 10¹⁴ Hz * λ
(2.04 * 10⁸ m/s) / (5.09 * 10¹⁴ Hz ) = λ
4.007*10⁻⁷ m = λ
The wavelength of the yellow light = 4.007*10⁻⁷ m
Answer:
9654.34 m
Explanation:
from conservation of momentum

And from Conservation of Energy

F=ma, so 100=m×10. Solve for m by dividing by 10. The mass is 10 kg.