David hits a ball with a stick so that it travels in a circle. Observe how he is hitting the ball.

Rutgers Physics Videos

 

 

 

#15 - Range of Possible Resultants

 

Ex) 100 N and 30. N  

 

Largest =

 

Smallest = ?

 

 

 

Largest Possible Resultant

 

= 130 N

 

Smallest Possible Resultant

 

= 70. N

 

 

 

Subtract

 

Smallest Resultant

 

Add

 

Largest Resultant

 

 

 

 

 

Ex) Which pair of concurrent forces may have a resultant of 20 nt?

a)  5 nt + 10 nt

b)  20 nt + 20 nt

 c)  20 nt + 50 nt

d)  30 nt + 5 nt  

 

 

Hint: Find the range of possible resultants for each choice

     

  Max   Min
a) 5 nt + 10 nt  15 nt 5 nt
b) 20 nt  +  20 nt  40 nt  0 nt
c) 20 nt  +  50 nt 70 nt 30 nt
d) 30 nt  + 5 nt 35 nt 25 nt

 

 

#16 Resultant, q = 90°

 

 

Pythagorean Theorum

Ex 1 ) A 5.0 N  north, 12 N force is pulling the object west.

Find the resultant

 

Scale 1 N = 1 cm

 

 

 

 

 

2. Make parallelogram

 

 

 

 

3. Draw diagonal (resultant)

 

 

4. Find magnitude & direction of vector

 

 

Method Two

 - Trig. and Pythagorean
(More accurate)

 

1. Use a2 + b2 = c2 (To find magnitude)

 

 

5.0 N2  + 12 N2  = R2


 

 

13 N  22.6 ° N of W 

 

 

E. Equilibrant - Balancing Force

 

 

 

 

 

Resultants & Equilibrants
St. Mary's Physics

 

 

 

The Equilibrant is always equal in magnitude and opposite in direction to the resultant

 

 

If…

 

 

Resultant  = 5 N 53° N of W

 

 

 

Then…

 

 

 

Equilibrant  = 5 N 53° S of E

 

 

 

 

 

 

 

1.  10 N2 + 10 N2 = c2

    

 

c = 14 nt

 

 

2.  R = 14 nt 45° S of E

 

 

 

Equilibrant  = 14 nt  45° N of W

 

 

 

 

 

 

  

© Tony Mangiacapre., -All Rights Reserved [Home] Established 1995 - Use any material on this site (w/ attribution)