A block of mass 10 kg is resting on horizontal surface when the force F is applied to it for 10 seconds as shown. The coefficient of friction between the block and ground is 0.50. The maximum velocity reached by the block is
In the figure, S is a small loudspeaker driven by an audio oscillator and amplifier, adjustable in frequency from 500 to 3000 Hz only. Tube D is a piece of cylindrical sheet-metal pipe 50.1 cm long and open at both ends. (a) If the speed of sound in air is 344 m/s at the existing temperature, at how many frequencies will a resonance occur in the pipe when the frequency emitted by the speaker is varied from 500 Hz to 3000 Hz? (b) What is the lowest resonant frequency in the given interval? (a) Number Units No units (b) Number Units
A 30 kg box is resting on an incline plane as shown in Figure Q2. The coefficient of static friction between the crate and the slope is 0.3 Figure Q2 a) Draw the free body diagram of the box and indicate clearly all forces acting on it. (4 marks) b) Determine the minimum force P to prevent the box from sliding down the plane. (10 marks) c) Determine the friction force between the box and the plane.
Shown in the figure below is a system containing two lenses and an object. The focal lengths of two lenses are f1 = 20 cm and f2 = -10 cm. The two lengths indicated in the figure are L1 = 30 cm and L2 = 16 cm. Determine all the following about the image from the first lens only: Object distance for the first lens, d01. cm Image distance for the first lens, di1. cm Magnification of the first lens, m1. The second lens uses the image from the first lens as its object. Determine all the following about the image from the second lens: Object distance for the second lens, d01. cm Image distance for the second lens, di1. cm Magnification of the second lens, m1. Determine the magnification of the whole system, mtot. Select the correct attributes of the final image of the system: virtual real enlarged shrunk right side up upside down NOTE: Throughout the problem be careful with the sign of every quantity.
When a click beetle is upside down on its back, it jumps upward by suddenly arching its back, transferring energy stored in a muscle to mechanical energy. This launching mechanism produces an audible click, giving the beetle its name. Videotape of a certain click-beetle jump shows that a beetle of mass m = 3.80×10−6 kg moved directly upward by 0.851 mm during the launch and then to a maximum height of h = 0.286 m. During the launch, what are the average magnitudes of (a) the external force on the beetle's back from the floor and (b) the acceleration of the beetle in terms of g? (a) Number Units (b) Number Units
A factory worker accidentally releases a 130 kg crate that was being held at rest at the top of a ramp that is 2.7 m long and inclined at 42∘ to the horizontal. The coefficient of kinetic friction between the crate and the ramp, and between the crate and the horizontal factory floor, is 0.30. (a) How fast is the crate moving as it reaches the bottom of the ramp? (b) How far will it subsequently slide across the floor? (Assume that the crate's kinetic energy does not change as it moves from the ramp onto the floor.) (c) Do the answers to (a) and (b) increase, decrease, or remain the same if we halve the mass of the crate? (a) Number Units (b) Number Units (c)
A wire radius a and b formed a closed circuit with radius a and radius b as shown in the figure. The circuit carries a current I. If the magnetic field is zero at the center point of P (or center of circular curves) then what is the ratio of a/b? (Attention: Be sure to mark the correct answer. If you mark a wrong answer, you will lose 20% of the pt.) a) 4/3 b) 2/3 c) 3/2 d) 7/2 e) 9/2
2. (5 Pts.) A very long straight wire carries a current of i = 1.8 A out of page (toward you). Imagine the wire is exactly at the origin of the coordinate system, as shown below. (a) (1) Show the magnetic field loop that goes through point P(3 m, 0 m) (b) (1) Show the exact direction of the B-field at point on the X-axis? (c) (3) What is the magnitude of the B-field at point