Mechanics | Relativity Answers

A carpenter on the roof accidentally drops the nail that hits the ground after 2.5 seconds. How high is the roof? What is the velocity of the nail just before hitting the ground?

A helicopter has to take a trip to deliver medicine at three locations. In the first leg it flies 620 km due east. In the second led it travels 440 km southeast (45°) and in the final leg it travels 53° south of west, for 550 km. Calculate the total displacement of the helicopter

A ball is thrown vertically upward with a speed of 15 m/s. Determine the time of flight when it

returns to its original position.

Consider the motion of a particle along a spiral given by r=R-Aθ [read as R minus A(theta)].The position of particle at time t=0 is r=R and θ=0. The speed of particle decreases linearly with time as v(t) =u - kt from time t=0 to t=u/k. What is the velocity as function of time in polar coordinates?

deternine the resultant of the following coplanar forces. 15N at 30 degress from the horizaontal, 55N at 80 degrees, 90N at 210 degrees, and 130N at 260 degrees

 A heartbroken fellow throws his engagement ring from the roof of a 20.0-m-tall building at an angle of  above the horizontal and with an initial speed of . Ignore air resistance and calculate:

a.     the maximum height above the roof of the building that the ring reaches;

b.    the speed of the ring before it reaches the ground;

c.     the horizontal range from the base of the building to the point where the ring strikes the ground.