FIGURE EX6.11shows the force acting on a 2.0kgobject as it moves along the x-axis. The object is at rest at the origin att=0s.What are its acceleration and velocity at t=6s?

Short Answer

Expert verified

At t=6s,

(a) Acceleration =0m/s2,

(b) Velocity =4m/s.

Step by step solution

01

(a) Acceleration : 

Acceleration is determined by the rate at which the velocity of an object changes over time.

02

(a) Explanation : 

The quantity of forceFexerted on an object is equal to the product of its mass mand the acceleration generateda, according to Newton's second equation of motion.

role="math" localid="1647763785550" F=maa=Fm

object's mass, role="math" localid="1647763846467" m= 2.0kg

initial velocityrole="math" localid="1647763903124" (u)=0m/s

force role="math" localid="1647763940636" F=0N, at time t=6s,

a=02a=0m/s2

Hence, acceleration at t=6sis0m/s2.

03

(b) Velocity : 

The pace at which an object's location varies in relation to time and a frame of reference.

04

(b) Explanation : 

For an object of massmhaving initial velocityuand final velocityvarea under forceF-timetgraph give change in momentum.

mv-mu=areaunderforce(F)-time(t)graph

v=areaunderforce(F)-time(t)graph+mum

object's mass, m= 2.0kg

initial velocity (u)=0m/s

force F=0N, at time t=6s,

v=4×3+-2×5-3+2×02v=12-4+02v=82v=4m/s

Hence, acceleration at t=6sis 4m/s. These values indicates that the object is moving with uniform velocity.

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