You need to be consistent about how you assign the positive directions. If you want positive to be up, what is the sign on y0? If you want positive to be down, what is the sign on the acceleration?KevinFan said:Homework Statement
A ball is tossed from an upper-story window of a building. The ball is given an initial velocity of 7.90m/s at an angle of 21.9deg below the horizontal. It strikes the ground 2.95s later.
Calculate the height from which the ball was thrown.
Homework Equations
The Attempt at a Solution
y=y0+vy0t- 1/2gt^2
vy0=sin21.9 deg*7.9m/s=2.9466m/s
0=y0+2.9466m/s(2.95s)-(1/2)(9.8m/s^2)(2.95s)^2
y0=33.95m
could anybody tell me where have done wrong?
Thank you:)Bystander said:Check your signs.
Projectile motion refers to the motion of an object that is launched into the air and then moves along a curved path due to the force of gravity. Common examples of projectiles include a ball being thrown, a plane taking off, or a rocket launching into space.
The key equations used to calculate projectile motion are the equations for displacement, velocity, and acceleration. These are:
- Displacement: d = v0t + 1/2at2
- Velocity: v = v0 + at
- Acceleration: a = g = 9.8 m/s2
Horizontal motion in projectile motion refers to the motion of the object in the horizontal direction, which is affected by the initial velocity and remains constant throughout the motion. On the other hand, vertical motion refers to the motion of the object in the vertical direction, which is affected by the force of gravity and changes over time.
The maximum height of a projectile can be calculated using the formula h = (v02sin2θ)/2g, where v0 is the initial velocity and θ is the launch angle. The range of a projectile can be calculated using the formula R = (v02sin2θ)/g.
The trajectory of a projectile can be affected by factors such as the initial velocity, launch angle, air resistance, and external forces. These factors can cause the projectile to deviate from its expected path and result in changes in its trajectory.