Why is the efficiency of a machine never 100%

A 2500-kg vehicle traveling at 25 m/s can be stopped by gently applying the breaks for 20 seconds. What is the average force supplied by the breaks to stop the vehicle?

Susie is measuring the different parts of a transverse wave and recording notes in her journal. Which of the following will she be able to measure using the crest or trough of a single wave? A.

A chemical reaction in witch more energy is absorbed than is released is endothermic

What is the kinetic energy of a 60kg jogger moving at a speed of 3m/s

If the average speed of a car is 45 km/hr, how far can it travel in 40 minutes?

Microwave ovens emit microwave energy with a wavelength of 12.3 cm. What is the energy of exactly one photon of this microwave radiation?

When light bounces off a surface, which component will be reflected more - the component that is parallel to the surface, or the component that is perpendicular to the surface, and why?

What is 18 degrees celsius in fahrenheit?

A small object moves along the x-axis with acceleration ax (t) = - (0.0320m/s3) (15.0s-t). At t = 0 the object is at x = - 14.0 m and has velocity v0x = 8.90 m/s. What is the x-coordinate of the object when t = 10.0 s?

Nitrogen and Hydrogen react to form ammonia (NH3). The reaction looks like this: Ammonia What is the ratio of nitrogen atoms to hydrogen atoms in ammonia? 1 to 2 1 to 3 2 to 1 3 to 1