The 85-lb force P is applied to the 200-lb crate, which is stationary before the force is applied. Determine the magnitude and direction of the friction force F exerted by the horizontal surface on the crate. (A) 100 lb (B) 85 lb (C) 75 lb (D) 60 lb
A uniform solid disk of mass m = 2.99 kg and radius r = 0.200 m rotates about a fixed axis perpendicular to its face with angular frequency 6.06 rad/s. (a) Calculate the magnitude of the angular momentum of the disk when the axis of rotation passes through its center of mass. kg⋅m2/s (b) What is the magnitude of the angular momentum when the axis of rotation passes through a point midway between the center and the rim? kg⋅m2/s
A wire loop of radius 18 cm and resistance 9.6 Ω is located in a uniform magnetic field that changes in magnitude as given in the figure. The loop's plane is perpendicular to the magnetic field. What is the magnitude of the emf in volts induced in the loop during the time intervals (a) t = 0 to 2.0 s; (b) 2.0 s to 4.0 s; and (c) 4.0 s to t = 6.0 s? (a) Number Units (b) Number Units (c) Number Units
A coin is placed 26 cm in front of a two-lens system. Lens 1 (nearer the coin) has focal length f1 = +14 cm, lens 2 has f2 = +18.7 cm, and the lens separation is d = 41 cm. For the image produced by lens 2, what are (a) the image distance i2, (including sign) and (b) the overall lateral magnification, (c) the image type (real or virtual), and (d) the image orientation (inverted relative to the coin or not inverted)? (a) Number Units (b) Number Units (c) (d)
In the figure, light initially in material 1 refracts into material 2, crosses that material, and is then incident at the critical angle on the interface between materials 2 and 3. The indices of refraction are n1 = 1.60, n2 = 1.40, n3 = 1.18. (a) What is angle θ? (b) if θ is increased, is there refraction of light into material 3? (a) Number Units (b)