Answer Happy

How many meters away is a cliff if an echo is heard 6.9 seconds after the m d - original sound? Assume that sound travels at 343.0-. HINT: v= → Solve t for d; What do we mean by the echo being heard one-half second after the original sound? O 1183.35 m O591.68 m O2366.70 m O 363.63 m

Question 10 5.57 pts When can we be certain that the average velocity of an object is always equal to its instantaneous velocity? O only when the acceleration is constant O only when the acceleration is changing at a constant rate always O only when the velocity is constant

Question 4 5.57 pts A ball is thrown directly upward and experiences no air resistance. Which one of the following statements about its motion is correct? O The acceleration of the ball is upward while it is traveling up and downward while it is traveling down. O The acceleration of the ball is downward while it is traveling up and downward while it is traveling down but is zero at the highest point when the ball stops. The acceleration is downward during the entire time the ball is in the air. O The acceleration of the ball is downward while it is traveling up and upward while it is traveling down.

Two runners approaching each other on a straight track have constant speeds m m of UL = 2.50, and UR = 1.50 respectively, when they are 4829.1 m 8 Ar apart. How long will it take for the runners to meet? Hint: t = VL+VR O 8048.50 s O 74368.14 m O 19316.40 s O 1207.28 s

Question 1 5.57 pts If the acceleration of an object is negative, the object must be slowing down. O True O False