Please help!
A truck is stopped at a stoplight. When the light turns green, it accelerates at 2.5 m/s2. At the same instant, a car passes the truck going 15 m/s. Where and when does the truck catch up with the car?
how do I even start???
A truck is stopped at a stoplight. When the light turns green, it accelerates at 2.5 m/s2. At the same instant, a car passes the truck going 15 m/s. Where and when does the truck catch up with the car?
how do I even start???
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Truck starts at rest and constantly accelerates at 2.5 m/s² while the car begins the race and continues it at constant speed.
truck's displacement = T =1/2at² {a = 2.5, t = time interval from when light turns grn}
car's displacement = C = 15t {where t = same time interval as in truck's formula}
at the instant truck catches car their displacements (from traffic light) must be the same so:
T = C at the time interval = t when truck catches car
1/2at² = 15t
cancel "t"
1/2at = 15
1/2(2.5)t = 15
t = 18.75 s = 19 s = interval of time for truck to catch car <= WHEN
U calculate WHERE by using either T or C formula, as both give same ans
truck's displacement = T =1/2at² {a = 2.5, t = time interval from when light turns grn}
car's displacement = C = 15t {where t = same time interval as in truck's formula}
at the instant truck catches car their displacements (from traffic light) must be the same so:
T = C at the time interval = t when truck catches car
1/2at² = 15t
cancel "t"
1/2at = 15
1/2(2.5)t = 15
t = 18.75 s = 19 s = interval of time for truck to catch car <= WHEN
U calculate WHERE by using either T or C formula, as both give same ans