Question

一道英文物理题 求解：

A car travels on a circular track of radius R = 217 m, with increasing speed v = R α t. [t = time; α = 0.09883 radians per second^2.]
(A) What is the angular position at t = 30 s (relative to t = 0) ? Express the answer in degrees between 0 and 360 degrees.
(B) Calculate the angular component of acceleration, aφ, at t = 30 s.
(C) Calculate the radial component of acceleration, ar, at t = 30 s.

Answer 1

A）Angular position: (1/2)α t^2 = (1/2)(0.09883)(30^2)(180/pi) = 2548.1 degrees, which is co-terminal to 28.1 degrees

B) aφ = dv/dt = R α = 217*0.09883 = 21.4 m/sec^2

C) ar = v^2/R = R(α t)^2 = 217(0.09883*30)^2 = 1907.6 m/sec^2

Answer 2

我怎么看觉得怎么奇怪啊，你是不是写得不对呀~~~~~~~