Question

Bianca is standing at x =600m. Firecracker 1, at the origin, and firecracker 2, at x =900m, explode simultaneously. The flash from firecracker 1 reaches Bianca's eye at 4.0 μs . Part A At what time does she see the flash from firecracker 2?

Answer 1

Answer:$3 \mu s$

Explanation:

Given

Bianca is at $x=600 m$

i.e. distance between origin and Bianca is $600 m$

time taken to reach Bianca eyes is

$t=\frac{600}{speed\ of\ light}$

$t=\frac{600}{3\times 10^8}$

$t=2\times 10^{-6} s$

$t=2 \mu s$

i.e. Cracker exploded at $t=2\mu s$ because it is observed at $t=4\mu s$

Time taken by second cracker flash to reach Bianca eyes

$t_2=\frac{300}{3\times 10^8}$

$t_2=10^{-6}$

$t_2=1 \mu s$

Therefore it will be observed at $t=3 \mu s$