A car has anacceleration of 20m/s^2, so what is the change of speed if it is driven for 10seconds?
2007-10-17 01:53:35 · 13 answers · asked by Paige 2 in Science & Mathematics ➔ Mathematics
lol so many different answers
2007-10-17 02:02:31 · answer #1 · answered by trenticles 2 · 0⤊ 2⤋
If no air resistance is present, the rate of descent depends only on how far the object has fallen, no matter how heavy the object is. This means that two objects will reach the ground at the same time if they are dropped simultaneously from the same height. This statement follows from the law of conservation of energy and has been demonstrated experimentally by dropping a feather and a lead ball in an airless tube. When air resistance plays a role, the shape of the object becomes important. In air, a feather and a ball do not fall at the same rate. In the case of a pen and a bowling ball air resistance is small compared to the force a gravity that pulls them to the ground. Therefore, if you drop a pen and a bowling ball you could probably not tell which of the two reached the ground first unless you dropped them from a very very high tower. Hope that helps =3
2016-05-23 03:34:04 · answer #2 · answered by hang 3 · 0⤊ 0⤋
You MUST remember the equations of motion, including
v=u+at, where v is the final velocity, u the initial velocity, a the acceleration, and t the time
Assuming u=0 the velocity after 10 seconds is 20x10 = 200m/s
The change of speed over the 10 seconds is therefore +200m/s
2007-10-17 02:05:46 · answer #3 · answered by Anonymous · 1⤊ 1⤋
Starting with the Position equation we have
X(t) = Xo + Vo*t + (1/2)(a)(t^2)
Taking the derivative with respect to time we obtain an equation for velocity (change in x/change in time).
V(t) = Vo + a*t
Because we are only looking for the change in velocity from t=0 to t=10 seconds we can assume Vo=0
Plugging in the given values we can obtain the answer:
V(t) = (20 m/s^2)*(10 s)
V(t) = 200 m/s
And if you wanted to know how far you traveled during that time: X(t) = (1/2)(a)(t^2) = (20 m/s^2)*(10 s)^2
X(t) = 1000 m
Because of the wording of the question we can't necessarily tell if they mean the change in velocity from t=0 to t=10...or the instantaneous change in velocity after 10 seconds. If what they want is the instantaneous change in velocity the answer is 20 m/s^2 , while the change in velocity from t=0 to t=10 is 200 m/s
Your safest bet would be to include both answers and an explanation for each.
2007-10-17 02:05:36 · answer #4 · answered by ok_ok361 3 · 2⤊ 2⤋
Acceleration of 20m per second per second, means every second it increases it's velocity by 20m per second.
0s speed = 0m/s; after 1s, speed = 20m/s; after 2s, speed = 40m/s etc. (40m/s means a distance of 40m every second)
The change in speed is the acceleration which is constant in this case - 20m/s^2
If you mean the difference in velocity after 10s then its 20x10 = 200m/s
2007-10-17 02:13:23 · answer #5 · answered by Simon D 5 · 2⤊ 0⤋
not sure if this is right but i figure 40 miles per second time 10 would be 4000 miles
another good answer would be the need for speed as times 60 would be 24000 miles pe hour
2007-10-17 02:07:44 · answer #6 · answered by George G 5 · 0⤊ 2⤋
Trick question!
The speed will be 200m/s, but the CHANGE IN SPEED (as your question refers to) will still be:
20m/s^2 (!!)
Nice try!
2007-10-17 02:01:26 · answer #7 · answered by Anonymous · 2⤊ 2⤋
Dead right Maussy, Manuel and all the 200 answers.
Maussy's shows the working.
2007-10-18 02:50:24 · answer #8 · answered by Sarah P 2 · 0⤊ 1⤋
It is half of the 20m/s^2.
2007-10-17 01:57:19 · answer #9 · answered by Anonymous · 0⤊ 3⤋
20*10=200m/s
2007-10-17 01:56:43 · answer #10 · answered by maussy 7 · 1⤊ 1⤋