Answer:
a) 103.32 m
b) 9.18 s
Explanation:
a) Let's use the knowledge that at the top of its trajectory, the baseball will have a final velocity of 0 m/s.
The acceleration due to gravity is -9.8 m/s², assuming the upwards direction is positive and the downwards direction is negative.
The initial velocity of the baseball is 45 m/s.
We are trying to find the vertical displacement of the baseball, Δx, and we have the variables v, a, and v₀.
Find the constant acceleration equation that contains all four of these variables:
Substitute the known values into the equation.
- (0)² = (45)² + 2(-9.8)Δx
- 0 = 2025 - 19.6Δx
- -2025 = -19.6Δx
- Δx = 103.32
The maximum height of the ball before it falls back down is 103.32 m.
b) Now we want to solve for time t. Find a constant acceleration equation that contains three known variables.
Substitute known values into this equation.
- 0 = 45 + (-9.8)t
- -45 = -9.8t
- t = 4.59183673
Remember that this is only half of the baseball's flight since we are using the final velocity for when the ball is halfway through its trajectory.
To solve for the total time the baseball is in the air, double the time t we solved for.
The baseball is in the air for 9.18 s.
Answer:
Velocity
Explanation:
Objects in motion usually have a speed which is scalar or velocity which is a vector.
A scalar quantity is one with magnitude but has no directional attribute.
A vector quantity is one with both magnitude and directional attribute.
Speed is a scalar quantity that describes the magnitude of motion a body accrues.
Velocity is a vector quantity that describes both the magnitude of motion and the direction of motion in a body.
Answer:
A. Rocket A will travel farther horizontally than rocket B.
Explanation:
This is because from the x axis, 40 m/s at 90 degrees travels directly vertical. 40 m/s at 70 degrees is slightly horizontal, so it will travel further horizontally.
They do have the same mass. However, “Heavy” implies we are concerned with how much force it takes to lift the object. In this case, we will find that the force needed to lift a kilo of feathers in air is slightly less than that needed to lift the kilo of lead.
