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Correct the following statement: “The racing car rounds a turn at a constant velocity of 90 miles an hour.”
Explain whether the following particles do or do not have an acceleration (a) a particle moving in a straight path with constant speed and (b) a particle moving around a curve with constant speed.
Suppose you are carrying a ball and running at constant speed, and wish to throw the ball and catch it back down. Should you (a) throw the ball at an angle of about 45º above the horizontal and maintain the same speed, (b) throw the ball straight up in the air and slow down to catch it, or (c) throw the ball straight up in the air and maintain the speed?
A projectile moves in a parabolic path without air resistance. Is there any point at which a parallel to v? perpendicular to v? Explain.
The boat is heading due north as it crosses a wide river with a velocity of 10 km/h relative to water. The river has a maintain velocity of 5 km/h due east. Determine the velocity of the boat with respect to an observer on the riverbank.
A railroad flatcar is travelling to the right at speed of 13 m/s relative to an observer on the ground. Someone is riding a motor scooter on the flatcar. What is the velocity of motor scooter relative to the flatcar if its relative velocity to the observer on the ground is (a) 18 m/s to the right? (b) 3 m/s to the left? (c) zero?
The compass of an airplane indicates that it is headed towards north, and its airspeed indicator shows that it is moving through air at 240 km/h. If there is wind of 100 km/h from west to east, what is the velocity of the airplane relative to earth?
A particle with velocity Vo = -3.8 i + 5.3 j (in m/s) at t = 0 undergoes a constant acceleration of magnitude 3.0 m/s2 at an angle of 130º from the +x-axis. What is the particle’s velocity at t = 5 sec?
A dog running in an open field has components of velocity Vx = 2.6 m/s and Vy = -1.8 m/s at time t = 10 sec. The dog is running with constant acceleration of 0.45 m/s2 and direction 31.0º measured from +x-axis. At 20 sec, (a) what are the x- and y-components of dog’s velocity? (b) What are the magnitude and direction of dog’s velocity?
A jet plane is flying at a certain altitude. At time t1 = 0, it has components of velocity Vx = 90 m/s, Vy = 110 m/s. At time t2 = 30 sec, the components are Vx = -170 m/s, Vy = 40 m/s. Calculate (a) the components of average acceleration, (b) the magnitude and direction of average acceleration.
