A big boulder has a mass of 8.20t (metric tons) and rests at a coal mine site. The boulder is blown up with explosives into 3 parts, all the 3 parts move horizontally in the xy plane. The biggest part (mass 3.3 t) travels west at a speed of 3m/s. The second part (mass 2.7t) moves at 2m/s in a direction 25.0 degrees south of east. What is the speed and direction of the third boulder part?

The velocities and masses of four objects are shown. Which object has the greatest inertia? D 5kg 3kg 4kg + 10 kg v=2m/s v=3m/s v=1m/s v=0m/s O D O A ов 4.

Problem 1. Part (a) You are in deep outer space, far away from any massive objects. You have two boxes, one of which is filled with lifesaving food while the other is empty. Unfortunately, you only have the means to open one of the boxes! But luck is on your side: you took PHYS 102! Using your conceptual understanding of physics, how will you determine which box to open? Part (b) An office has a 4-m x 5-m floor. If the total downward force on the floor is 2.2×106 N, then what is the air pressure in the room? Part (c) In which of the following scenarios is the total mechanical energy of the system conserved? Any objects that are underlined are included the system. There may be more than one correct answer, circle all that apply. (a) A plastic ball submerged in water floats to the surface. (b) A ballistic collides with and sticks to a pendulum. The two objects move together. (c) The Moon completes a full revolution around the Earth. (d) A ball sitting on the bottom of an incline…

A child with mass of 16.5 kg stands on the edge of a park bench and leaps into the air. Her initial speed is 2.4 m/s directed at an angle of 30 degrees above the horizontal. After 0.28 seconds what is the horizontal component of her velocity in m/s?