a uniform rod of mass m = 2.0 kg and length l = 1.5 m is pivoted at one end. a force of f = 10 n is applied…

a uniform rod of mass m = 2.0 kg and length l = 1.5 m is pivoted at one end. a force of f = 10 n is applied perpendicularly to the rod at its midpoint. what is the resulting angular acceleration of the rod?
Answer
Explanation:
Step1: 计算力矩
根据力矩公式(\tau = rF\sin\theta),力(F = 10N),力臂(r=\frac{L}{2}=\frac{1.5}{2}m),(\theta = 90^{\circ}),(\sin\theta = 1),则(\tau=\frac{1.5}{2}\times10) (= 7.5N\cdot m)。
Step2: 计算转动惯量
对于一端固定的均匀细杆,转动惯量(I=\frac{1}{3}mL^{2}),(m = 2.0kg),(L = 1.5m),则(I=\frac{1}{3}\times2\times(1.5)^{2}) (= 1.5kg\cdot m^{2})。
Step3: 计算角加速度
根据(\tau = I\alpha),可得(\alpha=\frac{\tau}{I}),将(\tau = 7.5N\cdot m),(I = 1.5kg\cdot m^{2})代入,(\alpha=\frac{7.5}{1.5}) (= 5rad/s^{2})。
Answer:
(5rad/s^{2})