What is the minimum luminous flux the lights should deliver

Reference no: EM13660764

A public school law requires a minimum illumination of 160 lx on the surface of all students’ desk. If the lights are 2.0 m above the desks, what is the minimum luminous flux the lights should deliver?

Reference no: EM13660764

Questions Cloud

How much liquid nitrogen boils away as the washer cools : In a physics lab, a student accidentally drops a 21.0-g brass washer into an open Dewar of liquid nitrogen at 77.2 K. How much liquid nitrogen boils away as the washer cools from 291 K to 77.2 K? The latent heat of vaporization for nitrogen is 199.1 ..

Magnitude of momentum impulse that the ball gave the wall : A tennis ball of mass m = 0.060 kg and speed v = 25 m/s strikes a wall at a 45-degree angle. It rebounds with the similar speed, once again at a 45-degree angle. What is the magnitude of the momentum impulse (in Ns) that the ball gave the wall?

Object orbiting the earth at a height above the ground : A pitcher throws a 0.145-kg baseball to a batter at 36 m/s. The batter hits the ball straight back at the pitcher at 49 m/s. The amount of time that the bat and ball are in contact is 9.0E-3s. What is the force (in N, assumed to be constant) among th..

What is the escape velocity from the sun : At low speed, air resistance is a force proportional to the velocity v of an object: F = -kv. Is this force conservative? What is the escape velocity (in m/s) from the Sun (M =2.0E30 kg) of an object that is a distance 9.1E7 km from the center of the..

What is the minimum luminous flux the lights should deliver : A public school law requires a minimum illumination of 160 lx on the surface of all students’ desk. If the lights are 2.0 m above the desks, what is the minimum luminous flux the lights should deliver?

What is the pressure change in water problem : What is the pressure change in water going from a 3.0- cm-diameter pipe to a 2.1- cm-diameter pipe if the velocity in the smaller pipe is 6.5 m/s?

What is the fundamental frequency of this pipe : A particular organ pipe can resonate at 264 Hz, 440 Hz, and 616 Hz, however not at any other frequencies between 264 and 616 Hz. (a) Is this an open or closed pipe? (b) What is the fundamental frequency of this pipe?

Compute buoyant force experienced by steel shell : Compute the buoyant force experienced by a steel shell totally submerged in fresh water.(The radius of the shell is70.0 cm and its mass is 1990kg.) What will occur if the shell is released (while experiencing this buoyant force)?

Electrical energy costs : If electrical energy costs 12 cents, or $0.12, per kilowatt-hour, then what would the following events cost? Burn a 60 W light bulb for 24 h straight. Operate an electric oven for 6.0 h if it carries a current of 20.0 A at 220 V.

User Account

All Pages