- #1
dorothy
- 39
- 1
- Homework Statement
- Does anyone knows how to solve these questions? Thanks a lot!
- Relevant Equations
- v=u+at
s=ut+1/2at^2
v^2=u^2+2as
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In part c, how far up the plane does the box go? What is its velocity at this point?dorothy said:Homework Statement:: Does anyone knows how to solve these questions? Thanks a lot!
Relevant Equations:: v=u+at
s=ut+1/2at^2
v^2=u^2+2as
View attachment 299486
Hi, I want to whether my answers on a & b are correct or not? For (c), I don’t really get the question, like what is the point of projection? How’s the deceleration and acceleration do in this case (c)? Thank you.Orodruin said:You seem to already have solved everything except (c), for which you have not shown any effort. What are your own thoughts regarding (c)?
Before that, I want to ask whether I understand question8 correctly? Is it true that there is a guy throwing(projecting) a box horizontally and the box finally land on the inclined plane(like what I have drawn)? Thank you.Chestermiller said:In part c, how far up the plane does the box go? What is its velocity at this point?
I don't agree with your answer to a). Acceleration is a vector, not a scalar.dorothy said:Hi, I want to whether my answers on a & b are correct or not?
Should (a) be -4.905?PeroK said:I don't agree with your answer to a). Acceleration is a vector, not a scalar.
This also affects the answer I would give to b) i) I).
Thaty said, it's not clear that the question setter acknowledges that acceleration is a vector.
That's what I would put. With the units as you have in your answer.dorothy said:Should (a) be -4.905?
I see. What about (b)? Are all of them correct?PeroK said:That's what I would put. With the units as you have in your answer.
I don't agree with b i) I).dorothy said:I see. What about (b)? Are all of them correct?
I expect the exercise composer means ##5## m/s along the incline, not ##5## m/s in a horizontal diertion.dorothy said:Before that, I want to ask whether I understand question8 correctly? Is it true that there is a guy throwing(projecting) a box horizontally and the box finally land on the inclined plane(like what I have drawn)? Thank you.
View attachment 299489
PeroK said:I don't agree with b i) I).
Sorry I meant b ii) I.dorothy said:May I know why bi) is not correct? I don’t know how to do it.
So higher acceleration gives smaller distance traveled until it turns around ... as OP stated.PeroK said:Sorry I meant b ii) I.
The acceleration has a greater magnitude in this case.
But if i assume the theta is 45° (which is greater than 30°, tilited more), then i put it into -9.81sin45°. I get the new acceleration=-6.9ms^-2. Next, I put 6.9 into the equation and get the new max distance =1.8 which is smaller than the original 2.55PeroK said:Sorry I meant b ii) I.
The acceleration has a greater magnitude in this case.
That right. It's like having more powerful brakes: you stop in a shorter distance.dorothy said:But if i assume the theta is 45° (which is greater than 30°, tilited more), then i put it into -9.81sin45°. I get the new acceleration=-6.9ms^-2. Next, I put 6.9 into the equation and get the new max distance =1.8 which is smaller than the original 2.55
So if the plane is tilited more, it becomes steeper, the distance traveled will also become smaller. Does it mean that I am actually correct on bii)1)?Orodruin said:So higher acceleration gives smaller distance traveled until it turns around ... as OP stated.
Does it mean that bii) I) is correct ?PeroK said:That right. It's like having more powerful brakes: you stop in a shorter distance.
Yes, sorry. I thought b ii) I was asking about the acceleration. I see now it's asking about the distance travelled.dorothy said:Does it mean that bii) I) is correct ?
No worries :) For part c, can you explain to me what is the meaning of reaching the point of projection? I don’t know which point it is. I’m super confused nowPeroK said:Yes, sorry. I thought b ii) I was asking about the acceleration. I see now it's asking about the distance travelled.
It was my fault.dorothy said:No worries :) For part c, can you explain to me what is the meaning of reaching the point of projection? I don’t know which point it is.
Probably the point where it was released with the original speed, but on the way down.dorothy said:No worries :) For part c, can you explain to me what is the meaning of reaching the point of projection? I don’t know which point it is. I’m super confused now
PeroK said:It was my fault.
I can only imagine that it means back at the bottom of the incline!
The SUVAT problem is a type of physics problem that involves a box or object moving on an inclined plane. It requires the use of the SUVAT equations, which are a set of equations that relate an object's initial and final velocities, acceleration, and displacement.
To solve a SUVAT problem, you first need to identify the known and unknown variables. Then, you can use the appropriate SUVAT equation to solve for the unknown variable. It is important to use the correct equation and to pay attention to units and directions when plugging in values.
The SUVAT equations are five equations that relate an object's initial and final velocities (u and v), acceleration (a), and displacement (s). They are: v = u + at, s = ut + 1/2at^2, v^2 = u^2 + 2as, s = 1/2(u+v)t, and s = vt - 1/2at^2. These equations can be used to solve for any of the five variables, as long as the other four are known.
To apply the SUVAT equations to a box on an inclined plane, you must first draw a free body diagram to identify the forces acting on the box. Then, you can use trigonometry to determine the components of the weight force and the normal force. These components can then be used in the SUVAT equations to solve for the acceleration and other variables.
Some common mistakes when solving SUVAT problems include using the wrong equation, not paying attention to units and directions, and not drawing a free body diagram to properly identify the forces acting on the object. It is also important to use consistent units throughout the problem and to round to the appropriate number of significant figures in the final answer.