Question

Find the answer and explain pls.
_____ 1.       An object in uniform circular motion has a constant

           A.       velocity      B. acceleration         C.       both of these D.       neither of these

_____ 5.     When a racecar rounds a circular banked corner at a constant speed, it has

A.       No tangential acceleration           B.       No centripetal acceleration

C.       both of these                                 D.       Neither of these

_____ 6.       On an unbanked road surface, the safe maximum driving speed for rounding a corner is directly proportional to the square-root of the radius of the curve.   The other physical parameter(s) that directly affect this maximum speed are

           A. the coefficient of static friction        B.       the mass of the car

           C. both of these                                      D.       neither of these

_____ 8. When applying Newton’s laws, the speed of a satellite in a stable orbit above a planet depends on

A.   the mass of the planet            B.       the mass of the satellite

           C. both of these                           D.       neither of these

Answer 1

Solution:

Q.1) When an object is in circular motion both velocity and acceleration are not constant. Hence option D should be right.

Q.5) When a car rounds it will have both tangential as well as centripetal acceleration. Hence option C should be right.

Q.6) Option A is right , as the formula for speed is v = sqrt(u r g) where u is coeficient of static friction.

Q.7) speed of satellite in a planet's orbit depends on planet mass

option A should be right.

please comment for queries.

thanks.