Which of the following materials is necessary to stop an alpha particle? a. three feet of concrete c. single sheet of aluminum foil b. three inches of lead d. single sheet of paper

what is the acceleration of a cabinet of a mass 45 kg if it is pushed by applying horizontal force of 25 Newtons and 18 Newtons

What is the resultant of a and b if a = 3i 3j and b = 3i - 3j?

Resonance occurs in the middle of the ear true of false

You set out to design a car that uses the energy stored in a flywheel consisting of a uniform 101-kg cylinder of radius r that has a maximum angular speed of 470 rev/s. the flywheel must deliver an average of 2.

What is the force exerted on a moving charge of - 2.0 μC at a 20° angle through a magnetic field of 3.0 * 10-4 T with a velocity of 5.0 * 106 m/s? 3.0 * 10-3 N 1.0 * 10-3 N 1.0 * 103 N

While a roofer is working on a roof that slants at 39.0 degrees above the horizontal, he accidentally nudges his 88.0 N toolbox, causing it to start sliding downward, starting from rest. If it starts 4.

Suppose that the centripetal force acting on an object in circular motion were doubled to a new value, and the object remained in a circular path with the same radius. How would the motion be affected?

2. Air at a temperature of 20 ºC passes through a pipe with a constant velocity of 40 m/s. The pipe goes through a heat exchanger in which hot gases outside the pipe heat up the air to 820 ºC.

What is the thermometer

In which natural cycle must an important gas in Earth's atmosphere be fixed before plants can use it? a. sulfur cycle b. carbon cycle c. nitrogen cycle d. oxygen cycle