MTH304 Quiz by Math Helper

MTH 304 · Assignment # 01 Solution · Math Helper

Q1. An 20N force acts on a 3kg box, which is in contact with a 5kg box on a smooth surface. Determine the contact force between them.

Solution:

determine contact force between them? First we find acceleration F=ma m=

)a a 2.5 find contact force

5(2.5)

12. 5

contact

contact F N kg kg

so F F m Now a

N

m · m · m m · m m · s m m · m · F · F

Q2. Two forces act on a point such that one force is twice the magnitude of the other. If their resultant is perpendicular to the smaller force. What would be the angle between the two forces?

Solution

and two forces such that and R R R.

common

we already assume let

as so R

Cos taking Cos Cos Cos Cos

as so Co

F · F · F · F · F F · F · F · F · F · F F · F F · F · F · F F · F · F · F · F · F · F · F · F · F

s

Cos

F

F

Q3. Find the magnitudes of two forces if their resultant is

5 N when they act at right angles, and 7 N when they act at an angle of 60°. of light=120N angle with horizontal

the light is in equilibrium so 0 and resolve tensions into components cos cos sin sin ap x y

x x y y weight

as

Now

Now

T · T · F · F · T · T · T · T · T · T · T · T

ply equilibrium condition Horizontal Equilibrium

cos cos

1. 7071 0.8165
2. 8660

sin sin the value of (0.8165 )sin sin

107. 6

Vertical

put

N a

T · T · T · T · T · T · T · T · T · T · T · T · T

we know 0.8165 put the value of 107.6 (0.8165)(107.6)

87. 9
88. 9 and 107.6

s so N

N hence N N

T · T T · T · T · T · T