Unformatted text preview: ME 240 Quiz 1 Review Concept Questions Particles A and B have the same constant speed v at point P. • What are velocity directions for A and B? • Are the particles accelerating? • If so, what are the acceleration directions for A and B? • Which particle is undergoing greater acceleration? The angular velocity and angular acceleration of the merry‐go‐round is as shown. Should the child walk inward or outward to not experience any sideways acceleration? The driver of the truck has a velocity v0 when the driver slams on the brakes and the truck comes to a stop. Frictional forces are insufficient to keep the crate A from sliding atop the truck bed. Consider the x‐ axis pointing to the right. During braking, The x component of the relative velocity v A / B is: a) >0, b) =0, c)<0 The x component of the relative acceleration a A / B is: a) >0, b) =0, c)<0 The friction force acting on the truck bed is in: a) +x dir, b) –x dir Compared to the case where the crate remains fixed on the truck bed, the truck requires: a)more time to stop, b) less time to stop, c) the same amount of time to stop. A car is being pulled to the right in the two ways shown. If the car is allowed to roll freely, there is no friction in the pulleys and the pulleys/rope have negligible mass Which situation will result in a greater car acceleration? ME 240 Quiz 1 Review Problems 1. A highway exit ramp is designed to be a circular segment of radius =130ft. The car exits at A traveling at 65mph and then decelerates to 25mph at B. Assuming the tangential acceleration is constant; compute the car’s speed and normal acceleration as a function of the arc length s. 2. A plane is approaching a runway along a trajectory =15deg. A radar antenna is monitoring the distance r and angle . When =20deg, r 216 ft / s , and 0.022 rad / s . Determine the distance r, planes speed vo, and the x and y components of velocity. 3. The motor M is turned on at t=0. Acceleration of the rope is uniform until it reaches a retraction rate of 4 ft/s at t=1s. Thereafter, the retraction rate is constant. Determine the tension in the rope for t>0. Cargo C weighs 130lb. ...
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- Spring '07
- 4 ft, 25mph, 15deg, 20deg, 65mph, 130ft