Question
1.If an arrow is shot upward on the moon with a velocity of 50 m/s its height (in meters) after t seconds is given by H = 50t - 0.66t2. With what velocity will the arrow hit the moon?
a. -49.5
b. -47
c. -50.1
d. -50
e. -51
2.If an arrow is shot upward on the moon with a velocity of 53 m/s its height (in meters) after t seconds is given by H = 53t - 0.62t2. When will the arrow hit the moon? Round the result to the nearest thousandth if necessary.
a. 85.484
b. 85.473
c. 85.489
d. 85.374
e. 85.485
a. -49.5
b. -47
c. -50.1
d. -50
e. -51
2.If an arrow is shot upward on the moon with a velocity of 53 m/s its height (in meters) after t seconds is given by H = 53t - 0.62t2. When will the arrow hit the moon? Round the result to the nearest thousandth if necessary.
a. 85.484
b. 85.473
c. 85.489
d. 85.374
e. 85.485
Answers
Steve
clearly, due to conservation of energy, etc., the arrow will strike with the same velocity as it left, but in the opposite direction.
just solve 53t - 0.62 t^2 = 0
t(53-0.62t) = 0
t = 53/0.62 = 85.4839
just solve 53t - 0.62 t^2 = 0
t(53-0.62t) = 0
t = 53/0.62 = 85.4839