So, please check my answers here:
1. Which example identifies a change in motion that produces acceleration?
A) A speed skater moving at a constant speed on a straight track**
B) A ball moving at constant speed around a circular track
C) A particle moving in a vacuum at constant velocity
D) A vehicle moving down the street at a steady speed
2. Objects in free fall near the surface of Earth experience
A) Constant speed
B) Constant velocity
C) Constant acceleration**
D) Constant distance
3. Suppose you increase your walking speed from 1 m/s to 3 m/s in a period of 1 s. What is your acceleration?
A) 2 m/s^2
B) 5 m/s^2
C) 4 m/s^2
D) 3 m/s^2**
4. The slope of a speed-time graph indicates
A) Direction
B) Acceleration**
C) Velocity
D) Speed
5. A train approaching a crossing changes speed from 25 m/s to 10 m/s in 240 s. How can the train's acceleration be described?
A) The train's acceleration is positive
B) The train is not accelerating
C) The train will come to rest in 6 minutes
D) The train's acceleration is negative**
6. What is a good definition of acceleration?
A) How fast a speed is changing at a specific instant**
B) How fast a velocity is changing at a specific instant
C) How fast a direction is changing at a specific instant
D) Each of the above
Are my answers correct? If not, let me know which ones aren't and I'll fix them. (✿◠‿◠)
answers?
Great job! Your answers are correct for questions 1, 3, 4, 5, and 6. However, in question 2, the correct answer is B) Constant velocity, not C) Constant acceleration. Objects in free fall near the surface of Earth experience a constant velocity since they accelerate due to gravity but at a constant rate. Keep up the good work! (｡•̀ᴗ-)✧
Great job! Your answers are mostly correct, but there are a couple of corrections needed:
1. The correct answer is actually B) A ball moving at constant speed around a circular track. This example involves a change in direction, which results in acceleration even if the speed remains constant. A speed skater moving at a constant speed on a straight track does not involve any change in motion that produces acceleration.
3. The correct answer is A) 2 m/s^2. Acceleration is calculated by dividing the change in velocity by the time taken. In this case, the change in velocity is 3 m/s - 1 m/s = 2 m/s, and the time is 1 s. Therefore, the acceleration is 2 m/s^2.
5. The correct answer is C) The train will come to rest in 6 minutes. The information given does not allow us to determine whether the train's acceleration is positive or negative. However, we know that the change in speed is from 25 m/s to 10 m/s, which means the train is decelerating (slowing down). The given time is 240 s, which can be converted to 4 minutes. So, the train will come to rest in 6 minutes.
Other than these corrections, your answers are correct! Keep up the good work! (◕‿◕✿)