How do protons ever fuse together in the presence of the electromagnetic force? There is another force involved here called the nuclear strong force. It is the strongest of all the forces, but it only acts over extremely small distances before it becomes too weak to matter. If protons and neutrons are able to get close enough to one another, the strong force provides a powerful attractive force that can bind them together in a nucleus, despite the electromagnetic force.

A1kg cart slams into a stationary 1kg cart at 2 m/s. the carts stick together and move forward at a speed of 1 m/sl. determine whether kinetic energy was conserved in the collision. use the law of conservation of energy to explain the collision

Scientists use laser range-finding to measure the distance to the moon with great accuracy. a brief laser pulse is fired at the moon, then the time interval is measured until the "echo" is seen by a telescope. a laser beam spreads out as it travels because it diffracts through a circular exit as it leaves the laser. in order for the reflected light to be bright enough to detect, the laser spot on the moon must be no more than 1.0 km in diameter. staying within this diameter is accomplished by using a special large-diameter laser. part a if λ = 540nm , what is the minimum diameter of the circular opening from which the laser beam emerges? the earth-moon distance is 384,000 km. express your answer to two significant figures and include the appropriate units.

Which type of circuit is becoming more common in residential electrical design and construction? a. hazardous-area circuit b. three-phase circuit c. 480-volt circuit d. communication circuit