A baseball player is running to second base at 5.03 m/s. When he is 4.80 m from the plate he goes into a slide. The coefficient of kinetic friction between the player and the ground is 0.180, and the coefficient of static friction is 3.14
What is his speed when he reaches the plate?
A) 1.96 m/s
B) 2.56 m/s
C) 4.47 m/s
D) 2.89 m/s
E) He stops before reaching the plate.
D
You might also like to view...
The figure shows a cross section of three parallel wires each carrying a current of 20 A. The currents in wires A and B are out of the paper, while that in wire C is into the paper. If the distance R = 5.0 mm, what is the magnitude of the force on a 2.0-m length of wire A?
A. 23 mN B. 64 mN C. 32 mN D. 46 mN E. 55 mN
The potential energy at x = 8 m is -2000 V and at x = 2 m is +400 V. What is the magnitude and direction of the electric field?
A) 200 V/m directed parallel to the +x-axis B) 300 V/m directed parallel to the +x-axis C) 400 V/m directed parallel to the +x-axis D) 500 V/m directed parallel to the +x-axis E) 600 V/m directed parallel to the +x-axis
The present motions of the planets were inherited from the rotation of the solar nebula
Indicate whether the statement is true or false
In a single-pass counterflow heat exchanger, 4536 kg/h of water enter at 15°C and cool 9071 kg/h of an oil having a specific heat of 2093 J/(kg K) from 93 to 65°C. If the overall heat transfer coefficient is 284 W/(m2°C), determine the surface area required.
GIVEN
• Oil and water in a single-pass counterflow heat exchanger
• Water flow rate m w= 4536 kg/h = 1.26 kg/s
• Oil flow rate m o= 9071 kg/h = 2.52 kg/s
• Inlet temperatures: Water (Tw,in) = 15°C Oil (To,in) = 93°C
• Oil outlet temperature (To,out) = 65°C
• Oil specific heat (cpo) = 2093 J/(kg °C)
• Overall heat transfer coefficient (U) = 284 W/(m2 °C)
FIND
• The surface area (A) required
ASSUMPTIONS
• Steady state
• Constant thermal properties
SKETCH
PROPERTIES AND CONSTANTS
the specific heat of water at 20°C (cpw) = 4182 J/(kg K)