i posted this earlier but got a confusing answer so pls help as best as u can asap!

True or False

1. If a 40 kg person is accelerating at 10 m/s2, then the magnitude of the force acting on him or her is 400 N.
(1 point)
true
false

Multiple Choice

2. How much force is needed to make a 60 kg object accelerate at a rate of 2.0 m/s2? (1 point)
62 N
62 kg
120 N
120 kg

3. What is the acceleration of a 30 kg object when 180 N of force is applied to it? (1 point)
6.0 m/s^2
60 m/s^2
210 m/s^2
5,400 m/s^2

4. Which of the following equations shows how you would solve for mass if you knew the force acting on an object and the acceleration of an object?
(1 point)
m = f/a
m = fa
m = a/f
m = f − a

soooooo need help!!! dunno what they are talking about! cant guess!
pls help asap!!!!!
thanx in advance

25 answers

This is all the same question, Newton's second law.
Force = mass * acceleration
THINK !!!
sry..... im actin real derpy right now
this is for 4. so the answer is b m=fa
kill me if i got that wrong
Looks like you need to brush up on one of the most basic and useful identities in mechanics:

F = ma
F(N) = m(kg) * a(m/s^2)
1 N = 1 kg-m/s^2

So, with that in mind,

#1: F = ma = 40kg * 10m/s^2 = 400 kg-m/s^2 = 400N

#2: F = ma = 60kg * 2m/s^2 = 120N
Note that you can eliminate two of the choices just based on the fact that they are not expressed in Newtons.

#3:180N = 30kg * a
(180 kg-m/s^2) / (30kg) = 6 m/s^2
Note that units cancel just like factors of numbers. That's how conversion factors work -- expressing some units in terms of other units.

Here, note that since
F = ma,
a = F/m = 180/30 = 6 m/s^2

#4:
Since F=ma, m = F/a
Don't forget your algebra I just because you're in physics now.
sry, im not that great at math even though this is science.
so the answers are
1. true
2. c
3. a
4. a
right...?

thanx Steve!:)
correct. At least it appears you can match up the provided answers with the lists of choices...
omg THANK YOU STEVE!!!!!
true 1 3 4
are these the correct answers
The correct answers are what Steve said.
10 m/s2
Thanks The correct answers are what steve said .... All of them are correct
True or False

1. If a 40 kg person is accelerating at 10 m/s2, then the magnitude of the force acting on him or her is 400 N.
(1 point)
true
false

Multiple Choice

2. How much force is needed to make a 60 kg object accelerate at a rate of 2.0 m/s2? (1 point)
62 N
62 kg
120 N
120 kg

3. What is the acceleration of a 30 kg object when 180 N of force is applied to it? (1 point)
6.0 m/s^2
60 m/s^2
210 m/s^2
5,400 m/s^2

4. Which of the following equations shows how you would solve for mass if you knew the force acting on an object and the acceleration of an object?
(1 point)
m = f/a
m = fa
m = a/f
m = f − a
True, 3, 1, 1. I just took the test.
Stop being n00bs
Thank you everyone.
1. True
2. C
3. A
4. A
Thanks everyone for all your help!
YAY!
True,C,A,A
Is totally correct, thanks , and TTR+S<3
Thank everyone soooo much who helped to get the answers!!!! :) <3333
Thanks guys so much!
Thank You!!!!!!!!!!!!!
True c,a,a
Yes, the answers are True, C, A, A.
"TTR+S<3" is 100% correct.

1. True
2. C
3. A
4. A
TTR+s<3 is correct.
The answers R

1. True
2. C
3. A
4. A
1.True
2.C-120 N
3.A-6.0m/s2
4.A-m=f/a