Mindblown: a blog about philosophy.

A cube of copper has a mass of 240g. Each side of the cube is 3.0cm long. Calculate the density of copper in gcm−3 and in kgm−3.

Water pouring from a broken pipe lands on a flat roof. The water is moving at 5.0 m s−1 when it strikes the roof. The water hits the roof at a rate of 10 kg s−1. Calculate the force of the water hitting the roof. (Assume that the water does not bounce as it hits…

A snooker ball strikes a stationary ball. The second ball moves off sideways, at 60° to the initial path of the first ball. Use the idea of conservation of momentum to explain why the first ball cannot travel in its initial direction after the collision. Illustrate your answer with a diagram.

A ball of mass 0.40kg is thrown at a wall. It strikes the wall with a speed of 1.5ms−1 perpendicular to the wall and bounces off the wall with a speed of 1.2ms−1. Explain the changes in momentum and energy which happen in the collision between the ball and the wall. Give numerical values where…

A trolley of mass 1.0kg is moving at 2.0ms−1. It collides with a stationary trolley of mass 2.0kg. This second trolley moves off at 1.2ms−1. a. Draw ‘before’ and ‘after’ diagrams to show the situation. b. Use the principle of conservation of momentum to calculate the speed of the first trolley after the collision. In…

A stone falls from the top of a cliff, 80m high. When it reaches the foot of the cliff, its speed is 38ms−1. a Calculate the proportion of the stone’s initial g.p.e. that is converted to k.e. b What happens to the rest of the stone’s initial energy?

Answer:- The value for sigma has to be to ensure that 95% of all readings are within the given range are 0.05. A probability distribution refers to the mathematical function in probability theory and statistics that delivers the odds of different possible scenarios for an experiment.

A newsstand has ordered five copies of a certain issue of a photography magazine. Let of individuals who come in to purchase this magazine. If X has a Poisson distribution with parameter , what is the expected number of copies that are sold?

Let p1 denote the probability that any particular code symbol is erroneously transmitted through a communication system. Assume that on different symbols, errors occur independently of one another. Suppose also that with probability p2 an erroneous symbol is corrected upon receipt. Let X denote the number of correct symbols in a message block consisting of…

A toll bridge charges $1.00 for passenger cars and $2.50 for other vehicles. Suppose that during daytime hours, 60% of all vehicles are passenger cars. If 25 vehicles cross the bridge during a particular daytime period, what is the resulting expected toll revenue? [Hint: Let of passenger cars; then the toll revenue h(X) is a…