In order to accelerate an objest must do which of the following?
change its speed during time interval
change its direction during a time interval
change its speed and direction during a time
any of the above
Any of the above.
To accelerate an object, it must change its speed and/or direction during a time interval. So, the correct answer is "change its speed and direction during a time."
In order to accelerate, an object must change its speed during a time interval, change its direction during a time interval, or change both its speed and direction during a time interval. So the correct answer is "any of the above."
Acceleration is defined as a change in velocity, where velocity is a vector quantity that includes both speed (magnitude of velocity) and direction. Therefore, for an object to accelerate, it needs to alter its velocity in some way. This can involve changing its speed (increasing or decreasing), changing its direction (turning or curving), or changing both its speed and direction simultaneously.
To determine which of these changes is occurring, you can analyze the object's motion over a given time interval. If the speed or direction changes, then acceleration is present. If neither the speed nor direction changes, then acceleration is not happening.