Physics -forces

bonkysleuth SG

when 2 forces are combined, the size of the resultant depends on the angle between the 2 forces.

which of the following can not be the magnitude of the resultant when forces of magnitude 3N and 4N are combined?

A 1N B 3N C 7N D 8N

I wrote B-3Newton. Is that right?

and secondly

A force of 3.0 N and a force of 4.0 N act on an object at the same time. which of the following forces cannot be the resultant force on the object?

A. 0.5 N B. 3.5 N c. 4.0N D. 5.0N

I wrote A. Correct me if there's any mistakes.thanks

airgrinder SG

when 2 forces are combined, the size of the resultant depends on the angle between the 2 forces.

which of the following can not be the magnitude of the resultant when forces of magnitude 3N and 4N are combined?

A 1N B 3N C 7N D 8N

I wrote B-3Newton. Is that right?

and secondly

A force of 3.0 N and a force of 4.0 N act on an object at the same time. which of the following forces cannot be the resultant force on the object?

A. 0.5 N B. 3.5 N c. 4.0N D. 5.0N

I wrote A. Correct me if there's any mistakes.thanks

I think the first one is 8N.

I'm not sure I understand the question on the second one.

airgrinder SG

For the first one, assuming 2D, absent of all other forces like gravity or friction. The max resultant force possible will be both 3N and 4N acting together in the same direction, hence 7N The min resultant force will be 3N and 4N in opposite direction, resulting a net of 1N. Hence my answer is 8N.

maurizio13 SG

3 + 4 will never be 8 even in the same direction

anakinfoo SG

First one is D - 8N.

Second is A - 0.5N

When two forces are acting together, the maximum resultant is when they are both pointing in the same direction.

--->--->

And the min. is when they are pointing towards each other.

---><---

Anything in between is achievable, we just need to place them at specific angles to each other.

I hope this answers your questions ><

aeskay SG

hmm interesting. does anyone know the explanation for the 2nd question? the question sounds pretty vague though

eagle SG

First one is D - 8N.

Second is A - 0.5N

When two forces are acting together, the maximum resultant is when they are both pointing in the same direction.

--->--->

And the min. is when they are pointing towards each other.

---><---

Anything in between is achievable, we just need to place them at specific angles to each other.

I hope this answers your questions ><

This answer is correct.

To further understand, draw out the vector force diagram.

davidche SG

For the first qn, the max you can get with a 3N and 4N force is only 7 N, therefore 8N is impossible.

For the second qn the lowest resultant force you can get is only 1N when 3N and 4N oppose each other.

3N---><---4N

Resultant:

<---1N

0.5N is impossible