D because friction will slow it down going up hills (for safety reasons) and you go really fast going down.
Translating the first sentence into equation we get, t = k(1/h)
where t is time in seconds, k is the constant and h is the horsepower. Substituting
the values in the equation we have, 12s = k(1/200) we have a k = 2400 seconds –
hp. To get the time at 240 hp we use the equation above and the constant, we
get, t = (2400 seconds-hp)(1/240hp) t = 10seconds.
Explanation:
Mechanical Waves are waves which propagate through a material medium (solid, liquid, or gas) at a wave speed which depends on the elastic and inertial properties of that medium.
Yes, acceleration only tells you how velocity is changing. It doesn't say anything about what velocity is at any given time.
For example, if you set your car to cruise control on the highway going 80 mph. That is a constant high velocity, yet the car has 0 acceleration.
The opposite is also true. After a red light turns green, you put foot on the gas to accelerate. However, your velocity is initially low even though it has high acceleration.
Answer:
because energy is used to keep the things in place