To answer these questions, we first need to understand the principles of projectile motion.
When a projectile is launched, it follows a curved path known as a parabola. The two main components of the projectile's motion are the horizontal motion and the vertical motion.
1. To find the actual initial speed of the projectile, we need to calculate its total initial velocity. This can be done using the Pythagorean theorem, which states that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides. In this case, the horizontal and vertical components of the velocity form a right triangle.
Therefore, we can calculate the initial speed as follows:
Initial speed = √(horizontal velocity^2 + vertical velocity^2)
In this case, the horizontal velocity is 20 m/s and the vertical velocity is 30 m/s.
So, the initial speed = √(20^2 + 30^2) = √(400 + 900) = √1300 ≈ 36.06 m/s.
2. As the projectile flies through the air, the horizontal component of its velocity remains constant. This is because there are no horizontal forces acting on the projectile (assuming no air resistance), so it will continue to move with a constant horizontal velocity.
3. The vertical component of the projectile's velocity changes due to the influence of gravity. Gravity pulls the projectile downward, causing it to accelerate in the vertical direction. As a result, the vertical velocity of the projectile decreases until it reaches its maximum height, where it momentarily becomes zero. After reaching the maximum height, the vertical velocity continues to decrease and then becomes negative as the projectile starts to fall back down.
4. At the projectile’s maximum height, its horizontal velocity remains the same as the initial horizontal velocity. This is because, as mentioned earlier, the horizontal component of the velocity remains constant throughout the projectile's motion.
5. At the projectile’s maximum height, the vertical component of its velocity is zero. This is because at the highest point of the projectile's trajectory, its vertical velocity reaches a maximum value of zero before it starts to decrease due to the downward pull of gravity.