(1) A man of mass 50 kg stands in a lift. Calculate the reaction of the floor of the lift on the man when the lift moves with an acceleration of 2 ms2 (a) upwards: (B) downwards. [Take g = 10.0 m 5-2 ]

Aball bearing at 220.0 °c is dropped into a cup containing 250.0 g of water at 20.0 °c. the water and ball bearing come to a temperature of 30.0 °c. what is the heat capacity of the ball bearing in j/°c? (hint: how are the algebraic signs of q related for the ball bearing and the water? )

Acid rain is caused by human activity. select the best answer from the choices provided t f

In 1859, charles darwin published the first edition of on the origin of species, which explained his observations of various groups of animals that showed great similarities but minor differences. darwin concluded that if a population of one species separates into two different populations that live in separate locations, then over the course of many generations the different populations can develop into different species. this idea predicted many future biological findings and became the basis of modern biology. darwin’s explanation for why different species exist is best described as a(n) law. theory. inquiry. hypothesis.