• ### A 15 kg projectile is launched at 374 m/s at a 55° angle to the horizontal. At the peak of its trajectory it c?

A 15 kg projectile is launched at 374 m/s at a 55° angle to the horizontal. At the peak of its trajectory it collides with a second projectile moving horizontally, in the opposite direction, at 136 m/s. The two stick together and land 9.6 km horizontally downrange from the first projectile's launch point. Find the mass of the second... show more
A 15 kg projectile is launched at 374 m/s at a 55° angle to the horizontal. At the peak of its trajectory it collides with a second projectile moving horizontally, in the opposite direction, at 136 m/s. The two stick together and land 9.6 km horizontally downrange from the first projectile's launch point. Find the mass of the second projectile. (answer in kg) I have no idea how to do this problem on my physics homework. please help, thank you.
1 answer · Physics · 5 years ago
• ### What do you think of my theory about how the universe began?

Here is my theory: "The world was created by a duck which was caught in a vacuum cleaner in space. The duck said 'let there be rocks!' and there was, Earth. But the world was sinful so the duck drowned everyone in his pee, after telling a man called Mr. Muhahahapacheleoszyzneyemielebokkawokkah… to build a big boat and put 2 of every... show more
Here is my theory: "The world was created by a duck which was caught in a vacuum cleaner in space. The duck said 'let there be rocks!' and there was, Earth. But the world was sinful so the duck drowned everyone in his pee, after telling a man called Mr. Muhahahapacheleoszyzneyemielebokkawokkah... to build a big boat and put 2 of every unicorn on it. For 69 days and 69 nights, the boat floated on the pee until on the 69th day, Mr. Muhahahapacheleoszyzneyemielebokkawokkah... saw a rainbow, which he was fairly sure was a sign that the duck would never need to go pee again. A few thousand years later, the duck saw the world was still evil. So the duck sent his bacon sandwich down to Earth to be eaten for our sins. It worked and now we are all one in holy duckliness." Where did the duck and the vacuum cleaner come from you might ask? Both are almighty and have always existed and will always exist. also, my duck says being gay is naughty and you shouldn't eat oysters. What do you think of my theory?? It is a very good theory right? Only sensible answers please! no trolls ;) Actually, trolls are welcome too!
5 answers · Physics · 7 years ago
• ### What is the relationship between area under a hisogram bar and frequency?

Frequency density
Frequency density
1 answer · Physics · 8 years ago

• ### What kind of wave is associated with particles , in wave particle duality?

I know It is not EM wave. It is not probablity wave since probablity can never be negative. But I think De Broglie's wave length for particles (like electron) is derived using equation of mass-energy equivalence. It infers that this wave carries energy ;for this wave-length is same as that of EM energy equivalent to the particle (E=mc^2).... show more
I know It is not EM wave. It is not probablity wave since probablity can never be negative. But I think De Broglie's wave length for particles (like electron) is derived using equation of mass-energy equivalence. It infers that this wave carries energy ;for this wave-length is same as that of EM energy equivalent to the particle (E=mc^2). Certainly the particle is not spontaneously changing to EM wave then again this EM wave somehow give rise to a particle. So why have we used this equation to find the wave nature of particle? What is it's significance? #Electron is both particle and wave. What kind of wave? It is a naive question from a novice and ignorant person, interested in quantum physics. please respond. Shrodinger's wave equation is related with a wave of complex value. Does the complex valued wave has the same wave-length as de-broglie's?
• ### Why is the speed of light 186,282 miles per second?

Why is it such a random number? Why not 578,532 miles per second, or 1,000,000 miles per second? Is there any signifcance to it? While we're on the subject, why are all the other physical constants the way they are? And why are they there in the first place? Were they determined by events in the creation of the universe, or have they existed... show more
Why is it such a random number? Why not 578,532 miles per second, or 1,000,000 miles per second? Is there any signifcance to it? While we're on the subject, why are all the other physical constants the way they are? And why are they there in the first place? Were they determined by events in the creation of the universe, or have they existed independent of anything else? Could the universe even exist without these constants? Speculation is welcome. My question may be a bit misleading in the way that it is worded. The real thing I want to get at is why does light cover THIS amount of distance, in THIS amount of time. You can ignore trivial things like units of measurment and just see the thing as a whole. Why is light THIS fast and not slower or faster? The same applies for all physical constants.

• ### Newton's cannonball?

Explain or critique the following statement. "Just like Newton's cannonball, the moon orbits the earth because it falls around the earth." Any help would be much appreciated!
Explain or critique the following statement. "Just like Newton's cannonball, the moon orbits the earth because it falls around the earth." Any help would be much appreciated!
• ### Which form of energy is stored in plannts?

a)solar energy b)mechanical energy c)chemical energy d) nuclear energy
a)solar energy b)mechanical energy c)chemical energy d) nuclear energy
• ### Did you know?

If you filled up a swimming pool full of mercury you could technically walk over it because it is so dense? IF we didn't die in 1 second.
If you filled up a swimming pool full of mercury you could technically walk over it because it is so dense? IF we didn't die in 1 second.
• ### Why do signs read "Dager High Voltage" rather than "Danger High current"?

the damaging effects of electric shock result from the amount of current that flows to the body, so why do signs read "Danger High voltage" and not "Danger high current"
the damaging effects of electric shock result from the amount of current that flows to the body, so why do signs read "Danger High voltage" and not "Danger high current"
• ### What are thesimple physics behind driving and driving safely? Please answer soon using kinematics and dynamics

I have been working my grade 11 physics project regarding the making of a slide show on physics of safe driving. I keep reading over notes and assignments and trying to incorporate what I have learned in kinematics (ie the kinematics equations) and dynamics. But it's just so hard for me. So far I have a few good slides. How do I incorporate... show more
I have been working my grade 11 physics project regarding the making of a slide show on physics of safe driving. I keep reading over notes and assignments and trying to incorporate what I have learned in kinematics (ie the kinematics equations) and dynamics. But it's just so hard for me. So far I have a few good slides. How do I incorporate subjects like the force of gravity Newton's laws of motion and other subjects into my presentation? Please answer my question as simply as you can and as quick as you can because my project is due soon!
• ### Why do we hear sound when tearing a paper?

the nature of the sound and its loudness is different when we tear a wet paper.
the nature of the sound and its loudness is different when we tear a wet paper.