A 2.4-kg mass and a 5.1-kg mass are attached to a massless cord that passes over a massless pulley...?
2020-08-03 1:13 pm
A 2.4-kg mass and a 5.1-kg mass are attached to a massless cord that passes over a massless pulley. What is the tension in the cord while the masses move freely? Ignore friction and drag.
回答 (1)
2020-08-03 2:33 pm
Take g = 9.8 m/s²
Refer to the figure below.
Consider the 2.4-kg mass:
F = ma
T - 2.4 × 9.8 = 2.4a
a = (T - 2.4 × 9.8)/2.4 …… [1]
Consider the 5.1-kg mass:
F = ma
5.1 × 9.8 - T = 5.1a
a = (5.1 × 9.8 - T)/5.1 …… [2]
[1] = [2]:
(T - 2.4 × 9.8)/2.4 = (5.1 × 9.8 - T)/5.1
5.1 × (T - 2.4 × 9.8) = 2.4 × (5.1 × 9.8 - T)
5.1T - 119.952 = 119.952 - 2.4T
7.5T = 239.904
Tension of the string, T = 32 N
Refer to the figure below.
Consider the 2.4-kg mass:
F = ma
T - 2.4 × 9.8 = 2.4a
a = (T - 2.4 × 9.8)/2.4 …… [1]
Consider the 5.1-kg mass:
F = ma
5.1 × 9.8 - T = 5.1a
a = (5.1 × 9.8 - T)/5.1 …… [2]
[1] = [2]:
(T - 2.4 × 9.8)/2.4 = (5.1 × 9.8 - T)/5.1
5.1 × (T - 2.4 × 9.8) = 2.4 × (5.1 × 9.8 - T)
5.1T - 119.952 = 119.952 - 2.4T
7.5T = 239.904
Tension of the string, T = 32 N
收錄日期: 2021-04-18 18:35:48
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