Help!

[krux]

Ok, for any of you intelligent people out there who wont give me a shit answer please reply to these questions for my science worksheet thing.

Explain why it is sometimes harder to drag a heavy object across a rough surface than to lift and carry the object over the surface?



and



Imagince that you are on a spaceship that is far from the sun or any planet. Explain why a 500 kg piece of equipment would be difficult to move, even though the object would be "weightless"?

and finally...


A 1 kg ball is dropped from a distance of 1 meter. A 5 kg ball is dropped from the same height. How does the acceleration of each ball compare? How do the unbalanced forces on each ball differ?




Alright thank you if you do answer, because I am really stumped on these questions.

[pharishall]

the first one is because friction

the second one is because its 500 kg its heavy everywhere

the third one if it is dropped from teh same height they will hit teh ground at the same time

[-=MuTT=-]

The item still weights 500kg. You're still going to need more then 500kg of force to move it. It'll still float and stuff, but it'l lstill wieigh 500kg as well.

[Slapdown]

Ok, for any of you intelligent people out there who wont give me a shit answer please reply to these questions for my science worksheet thing.

Explain why it is sometimes harder to drag a heavy object across a rough surface than to lift and carry the object over the surface?

If you were to lift an object, the only energy used would be to raise the object from the floor to the new height (Work Done = Force x Height). However, to drag the object along the floor, you have to constantly exert a force on it to keep that object moving, thus using more energy.



and



Imagince that you are on a spaceship that is far from the sun or any planet. Explain why a 500 kg piece of equipment would be difficult to move, even though the object would be "weightless"?

Mass and weight are different things. Mass is the how much the object weighs in kilograms. Weight is how many Newtons an object is, and is a vector quantity, because it is multiplied by gravity. 500 kg is a mass and therefore is always the same m**** but because gravity is different on different planets, its weight will vary.

and finally...


A 1 kg ball is dropped from a distance of 1 meter. A 5 kg ball is dropped from the same height. How does the acceleration of each ball compare? How do the unbalanced forces on each ball differ?

The accelerations differ because the masses differ. The 5kg ball has a greater gravitational force acting on it, and therefore pulls it down faster.



Alright thank you if you do answer, because I am really stumped on these questions.

My physics is bad, but this should help.

[liebherk]

Yea Slap, your physics is pretty bad.

Explain why it is sometimes harder to drag a heavy object across a rough surface than to lift and carry the object over the surface?

Friction. If you drag the object, friction is present, which is basically a force in the direction opposite of the one you're moving in. If you pick up the object, there's no resistance due to friction (besides air, which is usually too small to affect anything.)

The accelerations differ because the masses differ. The 5kg ball has a greater gravitational force acting on it, and therefore pulls it down faster.

Nooo! They fall at the same rate. Acceleration due to gravity is always the same no matter how much the object weighs. You can test it yourself with a ping pong ball and a golf ball.

Imagince that you are on a spaceship that is far from the sun or any planet. Explain why a 500 kg piece of equipment would be difficult to move, even though the object would be "weightless"?

It would be difficult to move because it has a lot of inertia, which is essentially resistance to change in movement. The more inertia an object has, the more force is necessary to get it moving. Inertia increases as mass increases, so a more massive object requires more force to move, no matter whether gravity is acting on it or not.

moved to homework, by the way.

[krux]

Thanks guys, I put it in off topic because nobody really comes in the homework section.

[Skaterdude]

Ok, for any of you intelligent people out there who wont give me a shit answer please reply to these questions for my science worksheet thing.

Explain why it is sometimes harder to drag a heavy object across a rough surface than to lift and carry the object over the surface?



and



Imagince that you are on a spaceship that is far from the sun or any planet. Explain why a 500 kg piece of equipment would be difficult to move, even though the object would be "weightless"?

and finally...


A 1 kg ball is dropped from a distance of 1 meter. A 5 kg ball is dropped from the same height. How does the acceleration of each ball compare? How do the unbalanced forces on each ball differ?




Alright thank you if you do answer, because I am really stumped on these questions.

1.Friction, the weight of the heavy object is lighter because it isnt being held back when you are carrying it, so it would be harder to drag it on a rough surface because of friction trying to hold it back.

2.Because even though there is no gravity, the mass of the object is still intact within the object.

3. (a)Newtons law says that every object has the same terminal velocity, so they would travel at the same speed and strike the ground at the same time.
(b)????

Dude i'm in 8th grade and I knew this shit...its not that hard if you just think about it.

[krux]

Thanks, and I have a couple more questions that im not too sure of.

To slapdown: So what does 1 newton equal?

To everyone else:

A ball is dropped off a ridge. At the same time, two more balls are kicked horizontally off the ridge. The third ball has a greater horizontal speed than the second ball. Because each ball travels the same distance in the vertical direction, accelerates with the same free fall acceleration, and has an initial velocity of 0 in the vertical direction, each ball reaches the ground at the same time, t.

A. Indicate how far each ball travels in the horizontal direction.


B. If the time interval is t, is 1.5 s, what is the horizontal speed of each ball?





Ok, a couple more questions:

If the car has a mass of 1260 kg, what is its momentum after it slows down?



What unbalanced force is necessary to produce the acceleration in (b)?





How long would it take the car to travel 3540m at the new velocity?















Alright thank you if you answer because I am really struggling with this physical science shit. I know people are going to say stuff like "why dont you learn it and stop being lazy" but I have honestly read the whole chapter like 3 times and cant grasp the concept. I need to know this stuff quickly, and if you guys can answer these questions, it would help me out ALOT.

Thanks

[Anti-Hero]

hahahaha physical science is what they make the remedial kids in our school take

[krux]

Im only a freshman. Im in physical science honors actually...

[mumkins]

Ok, for any of you intelligent people out there who wont give me a shit answer please reply to these questions for my science worksheet thing.

Explain why it is sometimes harder to drag a heavy object across a rough surface than to lift and carry the object over the surface?



and



Imagince that you are on a spaceship that is far from the sun or any planet. Explain why a 500 kg piece of equipment would be difficult to move, even though the object would be "weightless"?

and finally...


A 1 kg ball is dropped from a distance of 1 meter. A 5 kg ball is dropped from the same height. How does the acceleration of each ball compare? How do the unbalanced forces on each ball differ?




Alright thank you if you do answer, because I am really stumped on these questions.

no prob
for the first one, when you lift and carry the object the force you apply is perpendicular to the displacement of the object so you do no work on it. and because the object is on a rough surface friction would be opposing the motion and you'd need to apply more force to move it.

for the second one, its because of inertia. the object has a high mass and is at rest, so it would oppose a change in its motion.

for #3, the 2 objects fall at the same rate. however, the unbalanced forces are different in that the 5kg object has a fivefold greater gravitational force pulling it to the ground.

1 newton is equal to 1 kg.m/s^2 (F=ma)