Mechanics | Relativity Answers

Solve the

following word problems in kinematics. Show your complete solution!

1.     

A plane flies 955 km due east, then

turns to north and flies another 649 km. Determine the polar coordinates of the

plane’s final position.

2.     

The slowest animal ever discovered is a

crab found in the Red Sea that travels an average speed of 5.7 km/yr. How many

days will it take this crab to travel 1 meter?

3.     

A feather is dropped on the moon from a

height of 1.80 meters. The acceleration of gravity on the moon is 1.67 m/s^2.

Determine the time for the feather to fall to the surface of the moon.

4.     

An airplane accelerates down a runway

from rest at 2.65 m/s^2 for 36.86 s until is finally lifts off the

ground. Determine the distance traveled before takeoff.

A particle is displayed 60 cm to the north and then is given a second displacement of 90 cm to the east. what is the average velocity of the particle if it covers the displacement within 2.15 

6. An airplane travels 210km on a straight course at an angle 25 degrees east of north. It changes its course by moving 110 km north before reaching its destination. Determine the resultant displacement of the airplane. A.) Use graphical method B.) Use component method.

A rifle is aimed horizontally through Its bore at the center of a large target 150m away. The initial velocity of the bullet is 450 m/s. a) Where does the bullet strike the target? b) To hit the center of the target, the barrel must be an angle above the line of sight. Find the angle of elevation of the barrel. We assume frictionless system and g = -9,81 m/s^2. (Hint sin(2a) = 2sin(a)cos(a))

A box with mass 5kg, at the top of an inclined plane starts to slide down from its initial

resting position. The plane makes an angle of 25° with the horizontal surface.

i. Draw a Free-body diagram for the description above. Make sure it is neat and clear.(5marks)

ii. Derive a fomula for calculating acceleration with respect to the Net force, the frictional force and the force duc to the parallel plane. (3marks)

iii. Calculate thc acceleration (from equation in 'b') of the box if it slides down the plane,assuming a 7N friction force acting on the box due to the surface. (2Marks)

A man runs at a speed of 4,0m/s to overtake a standing bus. When he is 6,0 m behind the door (at t=0 s), the bus moves forward and continues with a constant acceleration of 1,2 m/s². a) Write the equation of motion ( x versus t) for both - men and bus. b) Draw these two functions x = x(t) using same coordinates system. Take t = 0s , 0.5s, 1.0s, 1.5s, 2.0s, 2.5s and 3.0s c) How long does it take for the men to gain the door? Solve this using the functions from part a.

a sky jumper speeds down a slope and exits the ski track in horizontal direction at a velocity of 25 m per second where the landing inclined falls of the slope of 33 °

solve the following

what is the halftime of flight of the sky jumper

what is the range of the sky jumper when it lands

A load W = 666 Kilonewtons is supported by two steel cables one of which makes an angle of 35o with the horizontal while the other makes an angle of 75o with the horizontal.

What is the Force or tension in NEWTONS of the 75o cable

A glider gliding from the top of a mountain to the ground at constant velocity. Draw a free body diagram.