Category: Physics

What is the angle of reflection for normal incidence? When a ray of light is incident normally on a plane mirror it means that the angle of incidence is 0ₒ. From the law of reflection, we find that angle of reflection is also 0ₒ. Thus, for normal incidence on a plane mirror, angle of incidence […]

How do rivers become larger as they travel across the land? 1 Answer. Tributaries combine, adding water to rivers. A tributary is a stream that flows into a larger river. Small streams from around an area combine together to form a bigger tributary that eventually falls into rivers. What kind of organism makes up the […]

Is it safe to live near an active fault why? The danger of living near fault lines Living near fault lines is inherently dangerous but difficult to avoid. The dangers people face include not only tremors but also other threats: Widespread smoke and ash can pollute the air and block out the sun for miles […]

Can you suddenly become farsighted? Signs and Symptoms of Presbyopia The most common symptom of presbyopia is the sudden onset of farsightedness, meaning that your near vision will be blurry while your distance vision will be clearer by comparison. What is worse nearsighted or farsighted? Nearsightedness means that your cornea might have a greater-than-average curvature, […]

What is the percentage of radioactive nuclei left after 3 Half Lives pass? Thus the half-life of a nuclear decay process is the time required for the number of unstable nuclei to decrease from [A]0 to 1/2[A]0….Radioactive Decay Rates. Number of Half-Lives Percentage of Reactant Remaining 2 50%2=25% 12(12)(100%)=25% 3 25%2=12.5% 12(12)(12)(100%)=12.5% n 100%2n (12)n(100%)=(12)n% […]

Can a body have zero velocity and still acceleration give example? Yes, a body with a velocity 0 can still accelerate. The simplest example is a body which is thrown up. At the peak point its velocity becomes 0 but still accelerates due to gravity. How can you have acceleration but no velocity? Since acceleration […]

What is a normal aerobic capacity? Exercise physiologists evaluate aerobic capacity in terms of how much oxygen you use when you’re exercising. This is called oxygen “uptake.” It’s reported as milliliters of oxygen per kilogram of body weight per minute, which is abbreviated “ml O2/kg/min.”… AGE MEN WOMEN • 90-94 yrs 6.1 – 10 laps […]

How much heat and pressure is needed for fusion? Fusion requires temperatures of about 100 million Kelvin (approximately six times hotter than the sun’s core). At these temperatures, hydrogen is a plasma, not a gas. Plasma is a high-energy state of matter in which all the electrons are stripped from atoms and move freely about. […]

What is the key difference between a physical and a chemical property? A physical property is a characteristic of a substance that can be observed or measured without changing the identity of the substance. Physical properties include color, density, hardness, and melting and boiling points. A chemical property describes the ability of a substance to […]

Can a vector have a negative direction? Vectors having the same length as a particular vector but in the opposite direction are called negative vectors. The magnitude, or length, of a vector, cannot be negative; it can be either be zero or positive. The negative sign is used here to indicate that the vector has […]