There are two pendulums with periods 1.5 s and 1 s, which one is longer, and which one is shorter.

The greater the length, the greater the period. Or vice versa

Explanation:

T = 2π * √ (L/g)

Given that T = 1s, g = 9.8m/s^2, π = 3.14

1 = 2 * 3.14 √ (L/9.8)

1 = 6.28 * L / 9.8

L = 9.8/6.28

L = 1.56m

When T = 1.5s

1.5 = 2*3.14√ (L/9.8)

1.5^2 = 6.28*L/9.8

2.25 = 6.28L/9.8

2.25*9.8 = 6.28L

22.05 = 6.28L

L = 22.05/6.28

L = 3.51m

From the above mathematical solution, it is clear that the greater the length, the greater the period. Or vice versa