A block of mass m1 = 4 kg is moving at 4 m/s and collides with a block of mass m2 = 2 kg, which is moving at 5 m/s in the opposite direction on a frictionless floor. After the collision, the blocks stick together and move as a single unit. a) [5 points] Determine the total kinetic energy of the system before the collision.

Imagine you are riding on a yacht in the ocean and traveling at 20 mph. you then hit a golf ball at 100 mph from the deck of the yacht. you see the ball move away from you at 100mph, while a person standing on a near by beach would observe your golf ball traveling at 120 mph (20 mph + 100 mph). now imagine you are aboard the hermes spacecraft traveling at 0.1c (1/10 the speed of light) past mars and shine a laser from the front of the ship. you would see the light traveling at c (the speed of light) away from your ship. according to einstein’s special relativity, how fast will a person on mars observe the light to be traveling? a) 0.1c (1/10 the speed of light) b) c (the speed of light) c)1.1c (c+0.1c)

Ihave a density of 1.61g/cm^3 and a mass of 28g. find the missing value

Give one example to show that when substances are mixed, it may result in a chemical or a physical change depending on the conditions.