Speed, Angle, Distance Homework HELP

AI Thread Summary
The discussion revolves around a physics homework problem involving projectile motion of a golf ball hit at an initial speed of 20.9 m/s and an angle of 43.5° on a flat field. Key points include the need to break down the initial velocity into horizontal and vertical components to solve for the distance the ball will fly and the maximum height it will reach. The problem also explores the effects of doubling the initial speed on the distance traveled and the time spent in the air. The professor emphasizes the distinction between speed and velocity, noting that only vertical motion is affected by gravity. Participants express confusion and seek clarification on applying kinematics equations to solve the problem.
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Homework Statement



After a golf ball is hit it takes off with an initial speed of 20.9 m/s and at an angle of 43.5° with respect to the horizontal. The golf field is flat and horizontal.

Neglecting air resistance how far will the golf ball fly?

How high will the golf ball rise?

How far would the ball fly if the initial speed was doubled?

How much time would the ball spend in the air in this second case?

Homework Equations



Professor posted this,

Once the ball leaves the shooter's hand it is in free-fall. Objects in free-fall have constant acceleration of 9.81 m/s2 DOWNWARD at all times while they are in free-fall. In addition, they have CONSTANT velocity in the horizontal direction (remember, constant velocity means acceleration in this direction is zero). Therefore, the larger the magnitude of the vertical component of the velocity, the higher the speed.

Also, speed and velocity are not synonymous. Speed (a scalar) is the magnitude of the velocity vector. Speed only has a magnitude/size, it has no direction and cannot be negative. Velocity has both a magnitude AND a direction. When references are made to the vertical component of the velocity vector in this problem, upwards is defined as the positive y direction; therefore 10 m/s upward is greater than 10 m/s downward (but the speeds associated with these two vertical velocities are equal)!

Didn't clarify anything for me, Please help.

The Attempt at a Solution



Having trouble and don't know what to do.
 
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Since you have an angle, you first want to break down the velocity into its component parts.
From there, use your kinematics equations.
 
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