At 100 km/hr, the car's kinetic energy is
KE = (1/2) (mass) (speed)²
KE = (1/2) (1575 kg) ( [100 km/hr] x [1000 m/km] x [1 hr/3600 sec] )²
KE = (787.5 kg) (27.78 m/s)²
KE = 607,639 Joules
In order to deliver this energy in 2.9 seconds, the engine must supply
(607,639 J / 2.9 sec) = 209,531 watts
<em>Power = 281 HP</em>
Answer:
Explanation:
Let the tension in the string be T . At the top of the circle , total force acting on them = T + mg . This will provide centripetal force
T + mg = m v² / r
4 + .25 x 9.8 = .25 x v² / .62
6.45 = .25 v² / .62
v² = 16
v = 4 m /s .
-- Light travels straight, not around in a circle. But if it did, it would cover
a distance equal to the length of the equator in about <em>0.13 second</em>.
-- At the speed of sound (in air at standard temperature and pressure),
it would take about <em>32.6 hours </em>to cover the same distance.
According to Newton second law of motion, the resultant force is directly proportional to the rate of change in momentum while maintaining other factors constant. Therefore, F = (mv-mu)/t where F is the resultant force , m is the mass of the object, v is the final velocity and u is the initial velocity.
Hence, Ft = mv-mu, but impulse is given by force multiplied by time, thus, impulse is equivalent to the change in momentum.
Impulse = Ft
= 325 × 2.2 sec
= 715 Ns