A cannon at ground level is firing at a fort 200m away with 20m high walls. It aims at an angle 30 degrees above the horizontal and fires cannonballs at 50m/s. Assuming no air resistance, will the cannonballs fall short, hit the walls or enter the fort?

solving horizontally, use v=s/t, where s=200, v=25(3)1/2. Hence t=s/v=8/(3)1/2 (where t is the time when the ball would reach the fort if it does not reach the ground)Solivng vertically, s=?, u=25, v is irrelevant, a=-9.8, t=8/(3)1/2, as we worked out from resolving horizontally. (s is the height of the cannonball when it reaches the fort)Use s=ut+(at2)/2. s=25(8/(3)1/2) + (-9.8)*(8/(3)1/2)2/2s=11m (2sf). 0<11<20. Hence, when the cannonball reaches the fort it is above ground but below the top of the wall, so it hits the wall.

Answered by Maths tutor

2614 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Solve 5x/(2x+1) - 3/(x+1) = 1


Differentiate x^2


Find dy/dx of y = a^x


Two masses A and B, 2kg and 4kg respectively, are connected by a light inextensible string and passed over a smooth pulley. The system is held at rest, then released. Find the acceleration of the system and hence, find the tension in the string.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences