Concept explainers
An object moving in a liquid experiences a linear drag force:
a. Find an algebraic expression for vx(t), the x-component of velocity as a function of time, for a spherical particle of radius R and mass m that is shot horizontally with initial speed v0through a liquid of viscosity ?.
b. Water at 20°C has viscosity ? = 1.0 × 10-3 N s/m2. Suppose a 4.0-cm-diameter, 33 g ball is shot horizontally into a tank of 20°C water. How long will it take for the horizontal speed to decrease to 50% of its initial value?
Want to see the full answer?
Check out a sample textbook solutionChapter 6 Solutions
PHYSICS FOR SCI/ENG:STRAT APPR V1 CUSTO
- Curling is a game similar to lawn bowling except it is played on ice and instead of rolling balls on the lawn, stones are slid along ice. A curler slides a stone across a sheet of ice with an initial speed vi in the positive x direction. The coefficient of kinetic friction between the stone and the curling lane is k. Express your answers in terms of vi, k, and g only. a. What is the acceleration of the stone as it slides down the lane? b. What distance does the curling stone travel?arrow_forwardA ball is thrown from point (0,0,0) with initial velocity v=vx0i + vy0j. The forces acting on theball are given as gravitational force F = −mg and air friction force Fs = −bv. Where b is thecoefficient of friction constant.a) Find the position and velocity of the ball as a function of time.b) What is the approximate distance from the origin when the ball lands?c) If the friction coefficient b is too small, what approximate the results you find in options a and b?Show it mathematically.arrow_forwardA hockey puck is hit on a frozen lake and starts moving with a speed of 12.3 m/s. Five seconds later, its speed is 6.60 m/s. (a) What is its average acceleration? (b) What is the average value of the coefficient of kinetic friction between puck and ice? (c) How far does the puck travel during the 5.00 s interval?arrow_forward
- The drag on a pitched baseball can be surprisingly large. Suppose a 145 g baseball with a diameter of 7.4 cm has an initial speed of 40.2 m/s (90 mph).a. What is the magnitude of the ball’s acceleration due to the drag force?b. If the ball had this same acceleration during its entire 18.4 m trajectory, what would its final speed be?arrow_forwardA block of mass 1.2 kg attached to a cord running over a pulley is dragged along a level surface by a hanging mass 0.2 kg, which was originally at rest. The coefficient of friction between the block and surface is 0.2. a) What is the tension in the cord? b) What is the acceleration of the system? c) How far down does the 0.2 kg mass descend in 3seconds?arrow_forward(a) What is the final velocity of a car originally traveling at 50.0 km/h that decelerates at a rate of 0.400 m/s2 for 50.0 s? Assume a coefficient of friction of 1.0. (b) What is unreasonable about the result? (c) Which premise is unreasonable, or which premises are inconsistent?arrow_forward
- (a) Calculate the acceleration (in m/s2) of a skier heading down a 19.7° slope, assuming the coefficient of friction for waxed wood on wet snow. (You can neglect air resistance, and you will find the equation for the acceleration of any object down an incline where fk = ?kN, a = g(sin(?) − ?k cos(?)), to be useful.) m/s2 (b) Find the angle (in degrees) of the slope down which this skier could coast at a constant velocity. (You can neglect air resistance, and you will find the equation for the acceleration of any object down an incline where fk = ?kN, a = g(sin(?) − ?k cos(?)), to be useful.)arrow_forwardD. what is the magnitude of the tension in the string connected to block M? E. what is the magnitude of the tension in the string connected to block m?arrow_forwardA 2000-kg pickup truck is moving at a speed of 40 m/s as its brakes are applied, and comes to a stop in 10 s. Assuming uniform acceleration, a) Draw a sketch of the scenario. b) what is the braking force applied to the truck? c). how far does the truck travel while the brakes are applied? d) What is the Normal force of the truck? e) Recalling that F(friction) = Mu(kinetic) x F(normal), calculate the coefficient of kinetic friction Mu?arrow_forward
- An elevator loaded with tourists has a mass of 1750 kg. a.) The elevator accelerates upward (in the positive direction) from rest at a rate of 1.55 m/s2 for 2.3 s. Calculate the tension in the cable supporting the elevator in newtons b.) The elevator continues upward at constant velocity for 8.5 s. What is the tension in the cable, in Newtons, during this time? c.) How far, in meters, has the elevator moved above its original starting point?arrow_forwardA contestant in a Winter games event pushes a 31.0 KG black of ice across a frozen Lake the coefficient of static friction is 0.1 in the coefficient of kinetic friction 0.3 calculate the minimum force he must exert to get the black moving? N What is the acceleration once it starts to move if that force is maintained? M/S2arrow_forwardA 15-kg sled is pulled across a horizontal, snow covered surface by a force applied to a rope at 30 degrees with the horizontal. The coefficient of kinetic friction between the sled and the snow is 0.20. (a) If the force is 33 N, what is the horizontal acceleration of the sled? (b) What must the force be in order to pull the sled at constant velocity?arrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning