Daisy raises 10.Kg to a height of 2.5 meters in 2.0 seconds
(a) How much work did she do?
(b) How much power was expended?
(c) If she raises it in 1.0 s rather than 2.0 s, how do the work and power change?
(a) 0.25 kJ
(b) 0.12 kW
(c) same work but power doubles
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A parent pushes a small child on a swing so that the child moves rapidly away while the parent remains at rest. How does the magnitude of the force that the child exerts on the parent compare to the magnitude of the force that the parent exerts on the child?
A. The force on the child is larger in magnitude. B. The force on the parent is larger in magnitude. C. These forces have equal magnitudes. D.The child exerts zero force on the parent. E.There is no way to tell.
Which of the following statements best describes the quantum property spin?
A) Spin is a measure of the rotation rate of a subatomic particle. B) Spin is a measure of the rate at which a particle spins around (orbits) another particle. C) Spin is a property that applies only to large objects, like baseballs. D) Spin is not meant to be taken literally but measures the inherent angular momentum of a subatomic particle. E) Spin is not a fundamental property but rather something that can change randomly at any time.
A spherical ball of lead (density 11.3 g/cm3 ) is placed in a tub of mercury (density 13.6 g/cm3 ). Which answer best describes the result?
A) The lead ball will float with about 17% of its volume above the surface of the mercury. B) The lead ball will float with about 83% of its volume above the surface of the mercury. C) The lead will sink to the bottom of the mercury. D) The lead ball will float with its top exactly even with the surface of the mercury.
Discuss how web designers create forms that follow UX principles.
What will be an ideal response?