Question #fc978
1 Answer
The height of the building: 45 m.
The angle of contact:
Explanation:
FULL QUESTION
A particle is projected horizontally from the top of a building in a velocity of
- What is the height of the building?
- What is the angle it creates with the horizontal when it hits the ground?
Like with any projectile motion problem, the basic idea is that your particle's trajectory can be broken down into a vertical and a horizontal component.
The same can be said for the particle's initial velocity. However, when you launch a particle horizontally, the nagle it makes with the horizontal is of course
The vertical component of the initial speed will be zero.
So, horizontally, the movement of the particle is not affected by any forces, which means that you can write
Plug your values into this equation to get the time of flight
The particle is in flight for only 3 seconds.
Vertically, the gravitational acceleration will affect the movement of the particle. This implies that vertical component of its velocity will increase as the particle descends from the building.
Taking into account that the vertical displacement is negative, you can write
To get the angle of contact with the ground, you need to determine the vertical component of its final velocity.
Use the equation
The horizontal component of the velocity is constant,
To get
Therefore,