A 6500-kg railroad car travels alone on a level frictionless track with a constant speed of 16.0 m/s. A 2500-kg load, initally at rest, is dropped onto the car.  What will be the car's new speed? Express your answer to three significant figures and include the appropriate units.

You wake up one morning to find yourself in a strange room with opaque walls, and no visible doors or windows. You decide to do some experiments to find out more about your strange situation. Your own body mass is 56.0 kg. You pick up an object and drop it from rest, starting at a height of 2.35 meters above the floor, and it hits the floor 0.346 seconds later. You can ignore air resistance. Based on the outcome of this experiment, when you step on the scale provided for you, what weight will it register for your body?     549.4 N     1,100 N     1,466 N     2,199 N

You wake up one morning to find yourself in a strange room with opaque walls, and no visible doors or windows. You decide to do some experiments to find out more about your strange situation. Your own body mass is 72.3 kg. You pick up an object and drop it from rest, starting at a height of 1.52 meters above the floor, and it hits the floor 0.223 seconds later. You can ignore air resistance. Based on the outcome of this experiment, when you step on the scale provided for you, what weight will it register for your body? 1 2,210 N 2 2,947 N 3 4,420 N 4 709.3 N

You wake up one morning to find yourself in a strange room with opaque walls, and no visible doors or windows. You decide to do some experiments to find out more about your strange situation. Your own body mass is 71.1 kg. You pick up an object and drop it from rest, starting at a height of 1.82 meters above the floor, and it hits the floor 0.305 seconds later. You can ignore air resistance. Based on the outcome of this experiment, when you step on the scale provided for you, what weight will it register for your body?     1,391 N     1,855 N     2,782 N     697.5 N