Question

A golf ball is struck with a velocity of 80 ft/s as shown. Determine the speed at which it strikes the ground at b and the time of flight from a to b

Answer 1

Explanation:

The initial velocity at which the ball is struck is:  

v

A

=

80

m

/

s

 

The angle of inclination of the surface is:  

α

=

10

∘

The angle at which ball is projected is:  

β

=

45

∘

The total angle of inclination of projectile from horizontal is

θ

=

α

+

β

Answer 2

Answer:

Speed at which it strikes the ground= 67.4ft/s

Time of flight= 3.57secs

Explanation:

(Va)x= 80cos(10+45)°= 44.886

(Va)y= 80sin(10+45)°= 65.532

S=So + Vot + 1/2at^2

d sin 10°= 0 + 65.532t + 1/2 (-32.2)t^2

0.17d= 0 + 65.532t + (-16.1)t^2

Solving the equation gives

d=166ft

t= 3.57seconds

(Vb)x= (Va)x= 45.886

(Vb)y= 65.532 - 32.2(3.57)

(Vb)y = -49.357

Vb= sqrt(45.886^2+(-49.357^2))

Vb= 67.4ft/s