a) We can find the time required for the motorcycle to change its speed from 20 m/s to 30 m/s from the kinematic equation:
"v=v_0+at_1,""t_1=\\dfrac{v-v_0}{a}=\\dfrac{30\\ \\dfrac{m}{s}-20\\ \\dfrac{m}{s}}{2.5\\ \\dfrac{m}{s^2}}=4.0\\ s."b) We can find the time required for the motorcycle to change its speed from 50 m/s to 60 m/s from the same kinematic equation:
"v=v_0+at_2,""t_2=\\dfrac{v-v_0}{a}=\\dfrac{60\\ \\dfrac{m}{s}-50\\ \\dfrac{m}{s}}{2.5\\ \\dfrac{m}{s^2}}=4.0\\ s."c) We can find the distance traveled by the motorcycle in each cases from the kinematic equation:
"d_1=v_0t_1+\\dfrac{1}{2}at_1^2,""d_1=20\\ \\dfrac{m}{s}\\cdot 4.0\\ s+\\dfrac{1}{2}\\cdot 2.5\\ \\dfrac{m}{s^2}\\cdot (4.0\\ s)^2=100\\ m,""d_2=v_0t_2+\\dfrac{1}{2}at_2^2,""d_2=50\\ \\dfrac{m}{s}\\cdot 4.0\\ s+\\dfrac{1}{2}\\cdot 2.5\\ \\dfrac{m}{s^2}\\cdot (4.0\\ s)^2=220\\ m."Answer:
a) "t_1=4.0\\ s."
b) "t_2=4.0\\ s."
c) "d_1=100\\ m, d_2=220\\ m."
Comments
Leave a comment