In this problem, we're asked to calculate the time when a plane should drop supplies to land on a target, given the plane's initial velocity and the height the package is dropped from.
For projectile motion problems in general, we'll follow these steps to solve:
If something is dropped from a horizontally moving vehicle, that means v0x is the same as the vehicle's velocity, and v0y=0. Basically, we can solve this in exactly the same way as a horizontal launch problem.
The four UAM (kinematics) equations are:
We define our coordinate system so that the +y-axis is pointing upwards and the +x-direction is horizontal along the launch direction. That means ay = −g, and ax = 0 (because the only acceleration acting on a projectile once it's launched is gravity.)
The pilot of an airplane traveling 170 km/h wants to drop supplies to flood victims isolated on a patch of land 160 m below. Assume the plane is moving purely horizontally.
The supplies should be dropped how many seconds before the plane is directly overhead?
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the Projectile Motion: Launch From Moving Vehicle concept. If you need more Projectile Motion: Launch From Moving Vehicle practice, you can also practice Projectile Motion: Launch From Moving Vehicle practice problems.