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particle has a constant acceleration of 5.8 m/s2. (Due to the nature of this problem, do not use rounded intermediate values in your calculations—including answers submitted in WebAssign.) (a) If its initial velocity is 2.1 m/s, at what time (in s after t = 0) is its displacement 4.0 m? (No Response) 0.867 s (b) What is its speed at that time (in m/s)? (No Response) 7.13 m/s

1 Answer

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Answer:

a) t = 0.86 sec

b) v = 7.128 m/s

Step-by-step explanation:

Given data:

Constant acceleration = 5.8 m/s^2

Initial velocity = 2.1 m/s

Displacement = 4.0 m

kinematic equation is given as


X -X_o = v_o * t + (1)/(2) at^2


X- X_o =  4.0 m

v = 2.1 m/s

a = 5.8 m/s^2

plugging all value in the above relation


4 =  2.1t + (1)/(2) 5.8t^2


2.9t^2 + 2.1t - 4 = 0

solve for t


t = (-2 \pm √(2.1^2 -(4* 2.9 * (-4)))/(2* 2.9)

t = 0.86 sec

b) kinematic equation relating to velocity is given as


v = v_0 + at

solving for velocity


v = 2.1 + 5..8* 0.867

v = 7.128 m/s

User Fletcher Johns
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