A hang glider moving at speed 6.31 m/s dives to an altitude 8.64 m lower. Ignoring drag, how fast is it then moving?
Question
A hang glider moving at speed 6.31 m/s dives to an altitude 8.64 m lower. Ignoring drag, how fast is it then moving?
Solution
To solve this problem, we can use the principle of conservation of mechanical energy. This principle states that the sum of kinetic and potential energy in an isolated system remains constant if only conservative forces are acting on it. In this case, we are ignoring drag, so the only force acting on the hang glider is gravity, which is a conservative force.
Step 1: Calculate the initial kinetic energy (KE) and potential energy (PE) of the hang glider.
The formula for kinetic energy is KE = 1/2 * m * v^2, where m is the mass of the object and v is its velocity. However, since we are not given the mass of the hang glider and we are only interested in the change in velocity, we can ignore the mass in our calculations.
The initial kinetic energy is therefore KE_initial = 1/2 * v_initial^2 = 1/2 * (6.31 m/s)^2.
The formula for potential energy is PE = m * g * h, where m is the mass of the object, g is the acceleration due to gravity, and h is the height. Again, since we are not given the mass of the hang glider and we are only interested in the change in velocity, we can ignore the mass in our calculations.
The initial potential energy is therefore PE_initial = 0, because the hang glider is at its highest point and we can set this as our reference point.
Step 2: Calculate the final kinetic energy and potential energy of the hang glider.
The final potential energy is PE_final = - m * g * h = - m * 9.8 m/s^2 * 8.64 m = - m * 84.672 J (we use a negative sign because the hang glider is below our reference point).
By conservation of energy, the final kinetic energy must be KE_initial + PE_initial - PE_final.
Step 3: Solve for the final velocity.
The final kinetic energy is KE_final = 1/2 * v_final^2. We can solve this equation for v_final to find the final velocity of the hang glider.
v_final = sqrt(2 * KE_final)
By plugging in the values we calculated earlier, we can find the final velocity of the hang glider.
Similar Questions
A ball rolls off a 5 meter high deck at 5 m/s. How fast will the ball be moving when it hits the ground?≈ 11 m/s≈ 8 m/s ≈ 9 m/s≈ 15 m/s
A boat moves downstream at the rate of 8 km per hour and upstream at 4 km per hour. The speed of the boat in still waters is:
What velocity is an object moving at after 4.0s if it is initially moving at 10.5m/s and is moving at 13.5m/s after 2.0s?
Object A moved 40 m in 1 minute while Object B moved 40 km in 1 minute.Which object was faster?
How long does it take a falling object (dropped from rest) to reach a downward velocity of 113 m/s?
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.