How big of a telescope do you need to see planets? Telescopes that have 4 or 5 inch diameters are great for viewing solar system objects like the planets, our Moon, and Jupiter’s moons. Viewing Neptune and Uranus can be difficult with a scope this small but it’s not impossible. A telescope of this size […]
How dangerous is a whirlpool?
How dangerous is a whirlpool? Whirlpools can be very dangerous and can cause drowning. Despite the danger, whirlpools are a fascinating natural phenomenon. Many people enjoy watching strong maelstroms spin away from the safety of dry land. Can you die from a whirlpool? The power of natural whirlpool is often exaggerated by fiction, as there […]
What should I do if my inverter battery is low?
Is Justified True Belief Knowledge Edmund gettier?
Is Justified True Belief Knowledge Edmund gettier? In his 1963 three-page paper titled “Is Justified True Belief Knowledge?”, Gettier attempts to illustrate by means of two counterexamples that there are cases where individuals can have a justified, true belief regarding a claim but still fail to know it because the reasons for the belief, while […]
What is the force acting on the ball?
What is the force acting on the ball? The forces are the weight, drag, and lift. Lift and drag are actually two components of a single aerodynamic force acting on the ball. Drag acts in a direction opposite to the motion, and lift acts perpendicular to the motion. What is the action force acting on? […]
What rate is the length of the shadow changing?
What rate is the length of the shadow changing? We’ve determined the instantaneous rate of change in the position of the shadow, which is -160 ft/sec, but that figure changes dramatically as the bird moves closer to the ground (and the mouse). In which case the length of the shadow of the tree will be […]
How can you tell if your 02 sensor is bad?
Why can you not fart in space?
Why can you not fart in space? The lack of gravity in space means the air in astronauts’ stomachs doesn’t separate from ingested food, so burping could expel more than just gas. Spaceflight missions also avoid serving high-flatulence foods, like Brussels sprouts and cabbage, to avoid “flammable butt gas” that’s hazardous in pressurized cabins. What […]
Is it possible to see radio waves?
Is it possible to see radio waves? The electromagnetic spectrum describes all of the kinds of light, including those the human eye cannot see. Other types of light include radio waves, microwaves, infrared radiation, ultraviolet rays, X-rays and gamma rays — all of which are imperceptible to human eyes. Why do pulsars spin so fast? […]
Why gravitation is always attractive?
Why gravitation is always attractive? In the case of gravity, mediated by spin 2 particles, charge is mass, which is always positive. Thus, q1q2 is always greater than zero, and gravity is always attractive. For spin 0 force mediators, however, there is no restriction on the charges and you can very well have repulsive forces. […]