FIGURE 6-15
-A 20.0-gram mass is attached to a 120 cm-long string as shown in Figure 6-15. The angle α is measured to be 18.0°. What is the speed of the mass?
A) 0.545 m/s
B) 1.95 m/s
C) 3.82 m/s
D) 1.18 m/s
E) 1.09 m/s

Question

FIGURE 6-15 
-A 20.0-gram mass is attached to a 120 cm-long string as shown in Figure 6-15. The angle α is measured to be 18.0°. What is the speed of the mass?
A) 0.545 m/s 
B) 1.95 m/s 
C) 3.82 m/s 
D) 1.18 m/s 
E) 1.09 m/s

Quizplus · Accepted Answer

The speed of the mass can be found using the formula for the speed of a pendulum at the lowest point: v = sqrt(2 * g * L * (1 - cos(α))), where g is the acceleration due to gravity (9.8 m/s²), L is the length of the string (1.2 m), and α is the angle (18°). Plugging in the values, the speed is approximately 1.09 m/s.

FIGURE 6-15 -A 20.0-Gram Mass Is Attached to a 120 Cm-Long String