Which science philosopher is credited for the invention of simple machines?

Which statements are examples of observations a scientist would make a classify rock? 1. a rock is larger than other rocks 2. a rock feels smooth to touch 3. a rock is formed from molten lava 4. a rock is made of different minerals 5.

A spherical hot-air balloon is initially filled with air at 120 kPa and 20°C with an initial diameter of 5 m. Air enters this balloon at 120 kPa and 20°C with a velocity of 3 m/s through a 1-m-diameter opening.

Blood pressure is measured when the blood is pumping (systolic) and when the heart is resting (diastolic). When pressure readings are given, the systolic is given first, and healthy blood pressure is around 120 over 80 mm Hg.

What factors might cause population changes in grasshoppers?

A car slows down from 23 m/s to rest in a distance of 85 m. what was its acceleration, assmed constant

A change from one form of energy into another is called a. gravitational potential energy. b. work. c. conservation of energy. d. an energy transformation

4. An airplane must achieve a velocity of 71 m/s for takeoff. If the runway is 1000 m long, what must the acceleration be?

As the average kinetic energy of the particles in a gas increases, which of the following occurs?

Power=170 watts time=20 seconds

What is the charge of alpha, beta and gamma rays?