Magnitude and Direction
Force is a Vector Quantity
As learned in an earlier unit, a vector quantity is a quantity that has both magnitude and direction. To fully describe the force acting upon an object, you must describe both the magnitude (size or numerical value) and the direction.
A force has both Direction and Motion.
For example, when finding acceleration you take the time and divided it by distance. If the thing you are measuring is going in the positive direction, the acceleration will be positive and if it is going in the negative direction the acceleration will be negative.
a) The initial momentum of the ball is 22.5 kg·m/s
b) The magnitude of the momentum imparted by the ball is 30 kg·m/s
The question is based on change in momentum
The mass of the ball, m = 0.75 kg
The velocity with which the ball is thrown against the wall, u = 30 m/s
The time duration it takes while the ball is in contact with the wall, Δt = 0.05 sec
The velocity of the ball as it bounce back, v = -10 m/s (The ball moves in the opposite direction)
a) The initial momentum of the ball, = m × u = 0.75 kg × 30 m/s = 22.5 kg·m/s
b) The final momentum of the ball, = m × v = 0.75 kg × (-10 m/s) = -7.5 kg·m/s
The momentum imparted by the ball, ΔP = The final momentum - The initial momentum
∴ ΔP = - = -7.5 kg·m/s - 22.5 kg·m/s = -30 kg·m/s
The magnitude of the momentum imparted by the ball, = 30 kg·m/s
The pH of a system is dependent on the concentration of hydrogen ions present in that system. The concentration of hydrogen ions in a solution is the amount of hydrogen ions (in the units of mol) present in a liter of solution.
Answer:Energy cannot be created or destroyed. It can be stored, or it can be transferred i.e. from a hot object to a cool object by conduction, convection or radiation.
D. On average, a woman's athletic ability peaks at a later age than a man's.