Explanation:
a) Power = work / time = force × distance / time
P = Fd/t
P = (85 kg × 9.8 m/s²) (4.6 m) / (12 s)
P ≈ 319 W
b) P = Fd/t
0.70 (319 W) = (m × 9.8 m/s²) (4.6 m) / (9.6 s)
m = 47.6 kg
Answer:
5694000 min
Explanation:
Let's suppose the average American watches 4 hours of TV every day. First, we will calculate how many minutes they watch per day. We will use the conversion factor 1 h = 60 min.
(4 h/day) × (60 min/1 h) = 240 min/day
They watch 240 minutes of TV per day. Now, let's calculate how many minutes they watch per year. We will use the conversion factor 1 year = 365 day.
240 min/day × (365 day/year) = 87600 min/year
They watch 87600 min/year. Finally, let's calculate how many minutes they spend watching TV in 65 years.
87600 min/year × 65 year = 5694000 min
Answer:
The cannonball and the ball will both take the same amount of time before they hit the ground.
Explanation:
For a ball fired horizontally from a given height, there is only a vertical acceleration on it towards the ground. This acceleration is equal to the acceleration due to gravity (g = 9.81 m/s^2). A ball dropped from a height will also only experience the same vertical acceleration downwards which is also equal to g = 9.81 m/s^2.
Therefore both the cannonball and the ball will take the same amount of time to hit the ground if they are released/fired from the same height.
