Explain why the efficiency of a simple machine cannot excced 100%

Sunlight appears white. However, rainbows, sunburn and the ability to see colors tell a different story. Explain what each of these tells us about the suns radiation and what property determines different colors.

When light reflects on a smooth surface it undergoes a change in? A. Speed B. Wavelength C. Frequency D. All of the above E. neither of the above

An 80-kg quarterback jumps straight up in the air right before throwing a 0.43-kg football horizontally at 15 m/s. how fast will he be moving backward just after releasing the ball?

The specific heat of a certain type of cooking oil is 1.75 J / (g⋅°C).1.75 J / (g⋅°C). How much heat energy is needed to raise the temperature of 2.34 kg2.34 kg of this oil from 23 °C23 °C to 191 °C?191 °C?

What are the principal features of the Moon observable with the unaided eye?

2. How is temperature related to kinetic energy?

As stream velocity decrease, which factor will likely increase? A) erosion of the stream bank B) deposition of material in the stream C) amount of material carried downstream D) size of the particles carried downstream

What cells in the nervous signals travel through the nervous system

A mechanic pushes a 3.60 ✕ 103-kg car from rest to a speed of v, doing 5,130 j of work in the process. during this time, the car moves 21.0 m. neglecting friction between car and road, find v and the horizontal force exerted on the car.

Anika asks Eva to roll a basketball and then a bowling ball to her. Which requires more force to roll, and why?