If an object accelerating at −1.5m/s^2 takes 1.2s to reach 5.0m/s, what was its initial speed?

Physics

1 answer:

USPshnik [31]2 years ago

3 0

-1.5 m/s^2 x 1.2 seconds = -1.8 m/s

It is a negative value which means the object slowed down. The object would have originally been going that amount more.

5.0 + 1.8 = 6.8 m/s

answer: 6.8 m/s

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b) The change in photon energy is given by:

$\Delta E=E_f-E_i=h\frac{c}{\lambda_f}-h\frac{c}{\lambda_i}=hc(\frac{1}{\lambda_f}-\frac{1}{\lambda_i})\\\\\lambda_f=4.04*10^{-12}m +\lambda_i=4.04*10^{-12}m+(0.0169*10^{-9}m)=2.09*10^{-11}m=0.0209nm$

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