A student fires a cannonball diagonally from the ground as shown. Neglect drag
and the initial height of the cannonball.
After the ball lands on the ground enter
zero for all speeds and heights if necessary.

The cannons total flight time is 2.23seconds

Explanation:

A ball fired diagonally is fired at an angle of 45° to the horizontal. The motion of the fired ball is a projectile motion. A projectile is a motion in which an object fired into space with an initial velocity U is allowed to fall freely under the influence of gravitational force.

To total time of flight T of the cannon ball can be expressed as;

T = 2Usin(theta)/g where;

U is the initial velocity or speed of the ball = 31m/s

theta is the angle that the ball make with the horizontal = 45°

g is the acceleration due to gravity = 9.81m/s²

Substituting the given datas into the formula we have;

T = 31sin45°/9.81

T = 31×0.7071/9.81

T = 21.92/9.81

T = 2.23seconds

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