1. Simple applications
Of 1st & 2nd Laws

2. Applications of Newton’s Laws
vo= 20 m/s
m = 5 kg
v = 0 F m d
Find distance
block moves
LIST! Vo V a d t

4. Determine the magnitude of the forces acting on each of the 2 kg masses at rest below.
30°
30°
30°
60°

5. ∑Fx = 0 and ∑Fy = 0
mg = 20 N
N = 20 N

6. ∑Fx = 0 and ∑Fy = 0
T1 = 10 N
20 N
T2 = 10 N

7. 30° mg = 20 N T1 = 20 N T2 = 20 N Method 1: ∑Fx = 0 and ∑Fy = 0

8. Method 1: ∑Fx = 0 and ∑Fy = 0 Method 2: ∑F = 0 30° T1 = 40 N T2 = 35 N

9. A Harder Problem! a. Which string has the greater tension?
b. What is the tension in each string?
30°
60°
Method 1: ∑Fx = 0 and ∑Fy = 0
Method 2: ∑F = 0

10. Applications of Newton’s Laws
Find Tensions T1 and T2 q
T1 sin(60)
T1 cos(60) T1 T2 mg m
q = 60o
m = 20 kg

11. Applications of Newton’s Laws
Another method q T1 q mg T1 T2 T2 mg m

14. Applications of Newton’s Laws
Three mass system - find acceleration F m 2m 3m
Find the tensions in the string.
First find the acceleration of the system.
Laws of Motion (Chapter 4) 2053.ppt

15. T2 F m 2m 3m Three mass system - find T2
Laws of Motion (Chapter 4) 2053.ppt

16. T1 T2 F m 2m 3m Three mass system - find T1
Laws of Motion (Chapter 4) 2053.ppt

17. Three mass system - find T1

18. Harder applications
Of 1st, 2nd & 3rd laws

19. If Hand force is 150N Find the acceleration of the system
With what force does the 5kg block push on the 10 kg block?