Can I know how to solve this physics question?

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1 Answer
May 11, 2018

Assuming that the ball was #120\ cm# above the ground when hit.

The initial velocity has horizontal and vertical components as

Horizontal: #v_(0x) = 40.0\ cos 26.0^@\ ms^-1#
Vertical: #v_(0y) = 40.0\ sin 26.0^@\ ms^-1#

Both components are orthogonal to each other, therefore these can be treated separately.

Time #t# taken by the ball to travel #110\ m# in the horizontal direction. Ignoring air resistance, horizontal velocity of ball remains constant.

#:. t = 110/(40.0\ cos26.0^@)\ s#

To calculate the height of the ball at time #t# can be found using the kinematic expression

#y = y_0 + ut + 1/2g t^2#

Noting that gravity acts in a direction opposite to the initial direction of vertical velocity, inserting various values we get

#y = 1.20 + (40.0\ sin26.0^@)xx110/(40.0\ cos26.0^@) +#
# 1/2xx(-9.81)xx(110/(40.0\ cos26.0^@))^2#
#=>y=1.20+53.650-45.981#
#=>y = 8.93\ m#

Fielder can reach #=3\ m# above the ground.
#:.# Height of ball passing above glove #= 8.93-3=5.93\ m #