> > > > Problem 26E

# A batter hits a baseball with mass 0.145 kg straight ## Problem 26E Chapter 6

University Physics | 13th Edition

• 2901 Step-by-step solutions solved by professors and subject experts
• Get 24/7 help from StudySoup virtual teaching assistants University Physics | 13th Edition

4 5 0 279 Reviews
13
0
Problem 26E

A batter hits a baseball with mass 0.145 kg straight upward with an initial speed of 25.0 m/s. (a) How much work has gravity done on the baseball when it reaches a height of 20.0 m above the bat? (b) Use the work-energy theorem to calculate the speed of the baseball at a height of 20.0 m above the bat. You can ignore air resistance. (c) Does the answer to part (b) depend on whether the baseball is moving upward or downward at a height of 20.0 m? Explain.

Step-by-Step Solution:

Solution 26E Introduction We have to calculate the work done using the force and displacement. Then we have to calculate the final kinetic energy and from that we can calculate the velocity of the ball at that height. Step 1 The gravitational force is given by w = mg = (0.145 kg)(9.8 m/s ) = 14.21 N This force will act vertically downwards and the displacement is vertically upwards. Hence the angle between the gravitational force and the displacement is 180°. So the work done by gravity is W = wdcos = (14.12 N)(2.00 m)cos(180°) = 28.24 J -28.24 J of work has been done by gravity on the ball. Step 2 The initial kinetic energy of the ball is And the work done, as calculated above, is W = 28.24 J. So the total energy kinetic energy of the ball at that height is Hence, if the velocity at that point2is v , then we have Hence the velocity at 2.0 m height will be 15.3 m/s.

Step 3 of 3

##### ISBN: 9780321675460

×
Get Full Access to University Physics - 13 Edition - Chapter 6 - Problem 26e

Get Full Access to University Physics - 13 Edition - Chapter 6 - Problem 26e

I don't want to reset my password

Need help? Contact support

Need an Account? Is not associated with an account
We're here to help

Having trouble accessing your account? Let us help you, contact support at +1(510) 944-1054 or support@studysoup.com

Password Reset Request Sent An email has been sent to the email address associated to your account. Follow the link in the email to reset your password. If you're having trouble finding our email please check your spam folder
Already have an Account? Is already in use