A projectile is fired out of a cannon at 50 km/s, at an angle of 30 degrees and an elevation of 10m from the ground. How long does it take for the projectile to hit the ground?

Find the verticle velocity by resolving the velocity vector:

Trigonometry: 50sin30 = 25m/s in upwards direction

Using SUVAT for the vertical direction: S=-10, U=25, A=-9.81, V=N/A, T=?:

s=ut+0.5at2 
In the upwards direction: -10=25(t)+0.5(-9.81)(t2) 

0 = -4.905(t2) + 25(t) +10

Solve quadratic using x = (-b+/-SQRT(b2-4ac))/2a

t = 5.47 seconds as negative solution cannot exist

LC

Related Physics A Level answers

All answers ▸

What is wave-particle duality?


Given a graph of the displacement of a particle, how can you tell if it is in Simple Harmonic Motion?


A piece of card is released from rest at a height of 0.5m above a light gate. It falls freely and a computer measures the velocity as it passes through the light gate to be 3.10m/s. What is the acceleration due to gravity measured by this experiment?


How would you calculate the vertical and horizontal components of the velocity of an object with an initial velocity of 15m/s which is travelling upwards at an angle of 30 degrees to the horizontal?