Knowing who writes the source is an important as long as the information is correct?

An electric bulb draws a current of 0.8A from 250 V mains. The bulb is used on an average 8 hours a day, If energy costs Rs 3 per kWh, calculate the monthly bill for 30 days.

Find the volume of a sphere which has 4 cm diameter

Julie is cycling at a speed of 3.4 meters/second. If the combined mass of the bicycle and Julie is 30 kilograms, what is the kinetic energy? A. 1.7 * 102 joules B. 1.5 * 102 joules C. 2.0 * 102 joules D. 2.2 * 102 joules

A biochemist studying breakdown of the insecticide DDT finds that it decomposes by a first-order reaction with a half-life of 12.0 yr. How long does it take DDT in a soil sample to decompose from 655 ppbm to 10.0 ppbm (parts per billion by mass) ?

Why might skin not be able to produce enough vitamin d

A 111.6 g sample of iron was heated from 0°C to 20°C. It absorbed 1004 J of energy. What is the specific heat capacity of iron?

A car is driving towards a brick wall at a constant velocity (don't try this at home!) and the driver honks the horn of the car. the sound of the horn reflects from the wall and the echo is heard by the driver.

Mass number of an atom with 11 protons

Which of the following elements is the most reactive? Beryllium Calcium Magnesium Barium

A flash of white light containing all the colors of the visible spectrum in air shines straight down on the surface of a pool.