Answer:
Step-by-step explanation: It would take him 15 minutes more to mow the whole yard
1/2 hour is 30 mins divided by 2 which is 15 mines times 3 is 45 mins total mins
Answer:
40 or 80%
Step-by-step explanation:
50 points / 2 points per questions = 25 questions
25 questions - 5 wrong answered questions = 20 right answered questions
20 right answered questions x 2 points each = 40 points in total
Answer:
8.5%
Step-by-step explanation:
.17/2 = 0.085 or 8.5%
Answer:cq cat cat cat cat
Step-by-step explanation:
Answer:
- KEi = 2.256×10^5 J
- KEf = 9.023×10^5 J
- 4 times as much work
Step-by-step explanation:
The kinetic energy for a given mass and velocity is ...
KE = (1/2)mv^2 . . . . . m is mass
At its initial speed, the kinetic energy of the car is ...
KEi = (1/2)(810 kg)(23.6 m/s)^2 ≈ 2.256×10^5 J . . . . . m is meters
At its final speed, the kinetic energy of the car is ...
KEf = (1/2)(810 kg)(47.2 m/s)^2 ≈ 9.023×10^5 J
The ratio of final to initial kinetic energy is ...
(9.023×10^5)/(2.256×10^5) = 4
4 times as much work must be done to stop the car.
_____
You know this without computing the kinetic energy. KE is proportional to the square of speed, so when the speed doubles, the KE is multiplied by 2^2 = 4.
