1. Can the kinetic energy of an object be negative?
2. In a collision between two cars, one car left skid marks twice the length of those left by the other car. A bystander who viewed the collision claims that the cars applied their brakes at the same time. What conclusions can you draw?
3. Two identical objects move with speeds of 5 m/s and 20m/s, what is the ratio of their kinetic energies?
2007-11-14 12:03:10 · 5 answers · asked by johnnyboy 2 in Science & Mathematics ➔ Physics
1. No. Kinetic energy has to be positive. m is positive and V squared has to be positive too.
2. The car that left longer skid marks covered more distance in the same time, so it was moving faster.
3. 16; One object moved 4 times faster than the other, and KE is proportional to v squared.
2007-11-14 12:13:24 · answer #1 · answered by olsonmus 2 · 0⤊ 0⤋
the concern with this simplistic analogy is that it quite is impossible to rigidity power to offer count. It happens at very small scales, yet because of the fact of entropy, loose power or power interior the form of light or warmth is a lot lots extra in all likelihood than power being forced to be based mass. The opposite technique, even nevertheless, is completed. Nuclear explosions are a effect of the opposite technique, it is, mass changing into power. it may be stated that no longer each and every of the uranium/plutonium mass is annihilated in a reaction, so which you do no longer see explosions which might cripple the international ( that little 9x10^sixteen joules you have up there). only a small volume of the textile honestly annihilates. to understand only how severe it is, only open a e book and seem on the mean existence of a particle at the same time with a pion, which supplies up the super majority of its mass whilst it decays into an electron/positron and photon.
2016-10-16 13:34:14 · answer #2 · answered by ? 4 · 0⤊ 0⤋
olsonmus is right.
In #2 it can be approximated that #2's original kinetic energy was 2X that of #1. So #2's speed was higher by a factor of sqrt(2).
2007-11-14 12:58:08 · answer #3 · answered by sojsail 7 · 0⤊ 0⤋
I only knew question 1's answer:
The answer for #1 is :
No kinetic energy can't be negative. But a change in kinetic can be negitive.
2007-11-14 13:24:32 · answer #4 · answered by #1_Physics_Girl 1 · 0⤊ 0⤋
#2 ONE HAD ANTI LOCK BRAKES
2007-11-14 12:12:40 · answer #5 · answered by Big ''D'' 3 · 0⤊ 0⤋