Answer:
6.5 m/s
Explanation:
We are given that
Distance, s=100 m
Initial speed, u=1.4 m/s
Acceleration, 
We have to find the final velocity at the end of the 100.0 m.
We know that
Using the formula
Hence, her final velocity at the end of the 100.0 m=6.5 m/s
The kinetic energy decreases
Answer:
meteor
Explanation:
A asteroid stays still and a meteor goes fast
This problems a perfect application for this acceleration formula:
Distance = (1/2) (acceleration) (time)² .
During the speeding-up half: 1,600 meters = (1/2) (1.3 m/s²) T²
During the slowing-down half: 1,600 meters = (1/2) (1.3 m/s²) T²
Pick either half, and divide each side by 0.65 m/s²:
T² = (1600 m) / (0.65 m/s²)
T = square root of (1600 / 0.65) seconds
Time for the total trip between the stations is double that time.
T = 2 √(1600/0.65) = <em>99.2 seconds</em> (rounded)
Answer: 11 km/h at 339° compass
Explanation:
A sees B moving south at 0 km/h
A is moving north at 12cos30 = 10.392 km/h
Therefore B must be moving north at 10.392 k/h
A is moving east at 12sin30 = 6 km/h
B appears to be moving west at 10 km/h
Therefore B must be moving west at 10 - 6 = 4 km/h
B is moving v = √(4² + 10.392²) = 11.135... 11 km/h
θ = arctan( -4 / 10.392) = -21.05 = 339°
