how do scientists know that black holes exist A. by running experiments on the sun B. by observing objects and light around black holes C. by viewing black holes with powerful telescopes D. all of the above E. none of the above

Philosophy is not considered science because it lacks: reason logic experimentation writing

Two organ pipes, both open at one end but closed at the other, are each 1.14 m long. One is now lengthened by 2 cm. Find the frequency of the beat they produce when playing together in their fundamental frequencies. A) 0.9 Hz B) 3.4 Hz C) 2.

You are given two positively charged particles, of equal magnitude, separated by a distance, "d". What will happen to the force field between the two particles when "d" is doubled?

The work of Charles Kuen Kao is likely to have been most influenced by the work of which of the following scientists? A. Christian Doppler B. Galileo Galilei C. Ibn al-Haytham D. Sir Isaac Newton

A block on an inclined plane experiences a force due to gravity of 300 N straight down. If the slope is inclined at 67.

What is the result of a mutation during replication A: the strands are different B: the strands are identical c: the strands are broken D: the strands are continuous

What is ___ heating of a liquid__ gas to liquid

A gate in an irrigation canal is constructed in the form of a trapezoid 2 m wide at the bottom, 38 m wide at the top, and 2 m high. It is placed vertically in the canal so that the water just covers the gate.

A machine with a mechanical advantage of 10 is used to produce an output force of 250 newtons. What input force is applied to this machine

Why do you float in space