You are told 3 things...1. That there are two objects with equal masses. 2. Both objects are in motion. 3. One object has a greater kinetic energy than the other. How is this possible? (1 point)
My apologies for the incorrect response earlier. Here is the corrected explanation:
If the two objects have equal masses but one has a greater kinetic energy than the other, it means that their velocities are different. Kinetic energy is directly proportional to the square of an object's velocity. So, even if the masses are equal, the object with a higher velocity will have a greater kinetic energy. Therefore, this is possible if one object is moving faster than the other.
A large truck and a small car are moving at the same speed,traveling up and down hills, and over bumpy roads. Which one has more kinetic energy?
1. The car has more kinetic energy because it moves fast down hill.
2. The truck has less kinetic energy because it has greater mass.
3. The car and truck have the same kinetic energy.
4. The truck has more kinetic energy because it has greater mass.
Which object has the greatest kinetic energy?
Reaspones
1. A green car with a mass of 500kg moving at a 21 m/s
2. A yellow car with a mass of 500 kg moving at a 12 m/s
3. A red car mass of 500 kg moving at 3 m/s
4. A blue car mass of 500 kg moving at 30 m/s
To determine which object has the greatest kinetic energy, you can use the equation KE = 0.5 * mass * velocity^2.
1. KE = 0.5 * mass * velocity^2 = 0.5 * 500 kg * (21 m/s)^2 = 0.5 * 500 kg * 441 m^2/s^2 = 110,250 Joules
2. KE = 0.5 * mass * velocity^2 = 0.5 * 500 kg * (12 m/s)^2 = 0.5 * 500 kg * 144 m^2/s^2 = 36,000 Joules
3. KE = 0.5 * mass * velocity^2 = 0.5 * 500 kg * (3 m/s)^2 = 0.5 * 500 kg * 9 m^2/s^2 = 2,250 Joules
4. KE = 0.5 * mass * velocity^2 = 0.5 * 500 kg * (30 m/s)^2 = 0.5 * 500 kg * 900 m^2/s^2 = 225,000 Joules
Based on the calculations, the blue car with a mass of 500 kg moving at 30 m/s has the greatest kinetic energy with 225,000 Joules. Therefore, the correct answer is option 4.
A wildlife keeper is trying to catch an escaping rabbit. Who has the greater kinetic energy, the rabbit or the wildlife keeper?(1 point) Responses
Wildlife keeper: 5 m/s 60 kg Rabbit: 5 m/s 4 kg
1. Neither one because they are moving at the same speed..
2. The wildlife keeper because they have a greater mass.
3. The wildlife keeper because they speed up and catch the rabbit.
4. The rabbit because it has less mass.
To determine which object has the greater kinetic energy, you can use the equation KE = 0.5 * mass * velocity^2.
For the wildlife keeper:
KE = 0.5 * 60 kg * (5 m/s)^2 = 0.5 * 60 kg * 25 m^2/s^2 = 750 Joules
For the rabbit:
KE = 0.5 * 4 kg * (5 m/s)^2 = 0.5 * 4 kg * 25 m^2/s^2 = 100 Joules
Based on the calculations, the wildlife keeper has a greater kinetic energy than the rabbit. Therefore, the correct answer is option 2. The wildlife keeper has a greater mass and thus, greater kinetic energy.
A skydiver jumps out of a plane and begins to accelerate. His speed increases to 20 m/s, then 30 m/s. His acceleration slows until he reaches a constant speed of 50 m/s. Which statement correctly describes his kinetic energy during this time?(1 point)
Responses
1. His kinetic energy increased while his speed increases, then it became constant
2. His kinetic energy increased quickly at first, then it increased at a constant rate.
3, His kinetic energy was positive at first, but it decreased to zero when he stopped accelerating.
4. His kinetic energy would remain the same for the whole fall as long as he lost no mass.
The correct response is:
1. His kinetic energy increased while his speed increases, then it became constant.
Kinetic energy is directly proportional to the square of velocity. As the skydiver's speed increases from 20 m/s to 30 m/s, his kinetic energy is increasing. However, once his speed reaches a constant 50 m/s, his kinetic energy also becomes constant because the velocity is no longer changing.