Positive if the acceleration is also upwards directed, and if you are considering a one dimensional space where you thus only have upwards and downwards as directions. Otherwise you need to more information before you able to answer this question.
Yes. Acceleration can be positive or negative. When he jumps out of the airplane and is in free fall, he is accelerating in a downward direction, so his acceleration is negative. When he opens his parachute, he accelerates in an upward direction, so his acceleration is positive.
An upward sloping straight line.
Yes it can, and it's really easy. -- A stone tossed upward, before it peaks and starts falling, has upward velocity and downward acceleration. -- A car driving east and slowing for a stop-sign has eastward velocity and westward acceleration.
That just means that the velocity and acceleration are in oppposite directions ... exactly the situation when a car is slowing down for a stop, or a ball is tossed upward and hasn't reached the peak yet.
Acceleration due to gravity is negative when an object is moving up. Accl'n due to gravity is positive when an object is moving down (since gravity acts downwards on an object). ^Acceleration due to gravity is always negative, while the acceleration of the ball upward was positive due to what threw it, not gravity.
If it is gravitational acceleration then it it is positive in downward and negative in upward direction..if it is not gravitational acceleration then it is depending upon the value of acceleration.
The sign of the acceleration is positive.
Yes. Acceleration can be positive or negative. When he jumps out of the airplane and is in free fall, he is accelerating in a downward direction, so his acceleration is negative. When he opens his parachute, he accelerates in an upward direction, so his acceleration is positive.
An upward sloping straight line.
Yes it can, and it's really easy. -- A stone tossed upward, before it peaks and starts falling, has upward velocity and downward acceleration. -- A car driving east and slowing for a stop-sign has eastward velocity and westward acceleration.
Acceleration and deceleration are related by their their sign. Acceleration is positive ( increase in velocity with time) and deceleration is negative (decrease in velocity with time).
That just means that the velocity and acceleration are in oppposite directions ... exactly the situation when a car is slowing down for a stop, or a ball is tossed upward and hasn't reached the peak yet.
Acceleration due to gravity is negative when an object is moving up. Accl'n due to gravity is positive when an object is moving down (since gravity acts downwards on an object). ^Acceleration due to gravity is always negative, while the acceleration of the ball upward was positive due to what threw it, not gravity.
An upward direction is usually considered positive.
a cricket ball is projected vertically upward direction.what kind of acceleration is acting on it
Yes, acceleration can be positive and negative because acceleration is a vector. It has both direction and magnitude. The direction is what makes it positive or negative. Negative acceleration is usually called deceleration.
The velocity has to increase in a positive direction. The increase in velocity in a positive direction is a positive acceleration.