A regulation basketball has a 6.9 cm diameter and may be approximated as a thin spherical shell. How long will it take a basketball starting from rest to roll without slipping 3.5 m down an incline that makes an angle of 57.0 ◦ with the horizontal? The acceleration of gravity is 9.81 m/s 2 . Answer in units of s.

Adolphin emits ultrasound at 100khz and uses the timing of reflections to determine the position of objects in the water. part a what is the wavelength of this ultrasound? assume that temperature of water is 20 degrees c. answer in cm

Achild has maximum walking speed of 1.6 m/s. what is the length of the child's legs? 0.26 m

The drag force, fd, imposed by the surrounding air on a vehicle moving with velocity v is given by fd = cdaρv 2/2 where cd is a constant called the drag coefficient, a is the projected frontal area of the vehicle, and ρ is the air density. an automobile is moving at v = 80 kilometers per hour with cd = 0.28, a = 2.3 m2, and ρ = 1.2 kg/m3.