Category: Physics

What four things do you need to check when taking measurements? When most people make a measurement, they assume it will be good enough….Four Steps To Ensure Measurement Data Quality What do you measure that’s important? How good do your measurements need to be? How do you know they are good enough? In the future, […]

Which surface has the most amount of friction? Rougher surfaces have more friction between them than smoother surfaces. That’s why we put sand on icy sidewalks and roads. You can’t slide as far across ice with shoes as you can on the blades of skates (see Figure below). The rougher surface of the soles of […]

What is the end result of cytokinesis? During cytokinesis, the cytoplasm of the cell is divided in half, and the cell membrane grows to enclose each cell, forming two separate cells as a result. The end result of mitosis and cytokinesis is two genetically identical cells where only one cell existed before. Does meiosis result […]

What mutation causes antibiotic resistance? Ribosomal mutations promote the evolution of antibiotic resistance in a multidrug environment. eLife, 2017; 6 DOI: 10.7554/eLife. 20420. What factors contribute to antibiotic resistance? In summary, the 6 main causes of antibiotic resistance have been linked to: Over-prescription of antibiotics. Patients not finishing the entire antibiotic course. Overuse of antibiotics […]

What is the leak rate threshold for comfort cooling appliances? Owners/operators must identify and repair leaks that exceed 30% for IPR, 20% for commercial refrigeration, and 10% for comfort cooling and other appliances within 30 days of when the ozone- depleting refrigerant is added. Leaks must be repaired such that the leak rate is brought […]

How dangerous is 200 Roentgen? Radiation Effects on Humans Dose (rem) Effects 100-200 Mild radiation sickness within a few hours: vomiting, diarrhea, fatigue; reduction in resistance to infection. 200-300 Serious radiation sickness effects as in 100-200 rem and hemorrhage; exposure is a Lethal Dose to 10-35% of the population after 30 days (LD 10-35/30). How […]

What is the use of velocity? The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of an object’s speed and direction of motion (e.g. 60 km/h to the north). How do you […]

What is the percentage of having a carrier female offspring? A woman who is a carrier has: a 25% (one in four) chance of having a daughter who is a carrier. How does a girl become a carrier of hemophilia? A female who inherits one affected X chromosome becomes a “carrier” of hemophilia. She can […]

How do you find the specific heat of ice? Calculate specific heat as c = Q / (mΔT) . In our example, it will be equal to c = -63,000 J / (5 kg * -3 K) = 4,200 J/(kg. K) . This is the typical heat capacity of water. What is the specific heat […]

How do you explain the slope? Slope is calculated by finding the ratio of the “vertical change” to the “horizontal change” between (any) two distinct points on a line. Sometimes the ratio is expressed as a quotient (“rise over run”), giving the same number for every two distinct points on the same line. What is […]