All vehicles are required to stop within 15 FEET of the railroad crossing when a train is approaching.
vf = 10 m/s. A ball with mass of 4kg and a impulse given of 28N.s with a intial velocity of 3m/s would have a final velocity of 10 m/s.
The key to solve this problem is using the equation I = F.Δt = m.Δv, Δv = vf - vi.
The impulse given to the ball with mass 4Kg is 28 N.s. If the ball were already moving at 3 m/s, to calculate its final velocity:
I = m(vf - vi) -------> I = m.vf - m.vi ------> vf = (I + m.vi)/m ------> vf = I/m + vi
Where I 28 N.s, m = 4 Kg, and vi = 3 m/s
vf = (28N.s/4kg) + 3m/s = 7m/s + 3m/s
vf = 10 m/s.
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<u>Yes. The speed of a rocket can exceed the exhaust speed of the fuel.</u>
How this is explained?
- The thrust of the rocket does not depend on the relative speed of the gases or the relative speed of the rocket.
- It depends on conservation of momentum.
What is conservation of momentum?
- Conservation of momentum, general law of physics according to which the quantity called momentum that characterizes motion never changes in an isolated collection of objects; that is, the total momentum of a system remains constant.
- Momentum is equal to the mass of an object multiplied by its velocity and is equivalent to the force required to bring the object to a stop in a unit length of time.
- For any array of several objects, the total momentum is the sum of the individual momenta.
- There is a peculiarity, however, in that momentum is a vector, involving both the direction and the magnitude of motion, so that the momenta of objects going in opposite directions can cancel to yield an overall sum of zero.
To know more about conservation of momentum, refer:
brainly.com/question/7538238
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Answer:
Heat required = mass× latent heat Q = 0.15 × 871 ×
Answer:
Negative acceleration occurs when the acceleration vector points to the left.
1. Object slowing down in the positive direction.
2. Object speeding up in the negative direction.
Following six statements:
1. T
2. F
3. T
4. T
5. F
6. T
Check direction of acceleration vector.
