Answer:
280 N
Explanation:
acceleration = v2-v1 / time taken = (2-4 )/ 0.05 = -40 m/s^2 ( neg sign indicates slowing down )
force exerted = ma = 7 kg x -40 m/s^2 = - 280 N ( neg sign means opposite direction of initial velocity )
since the 7 kg ball is slowing down, the direction of force will be opposite of the initial velocity , and it will be 280 N
Answer:
i got b but urs is a little different tell me if right
Explanation:
i go 100 on my test
<span>.87 m/s^2 ,hope this helps!!!!!!</span>
Answer:
(a)The work done by the man is -15.03J.
(b)The force exerted on the object is 127.4N.
Explanation:
Mass of the object pulled by the man is -13kg
Object is lifted 11.8 cm vertical with his teeth it means (displacement = +11.8cm = +0.118m)
Acceleration due to gravity is 
(a) <u>Calculating the work done</u>:
Work done = mgh
Where "m" is mass of an object, "g" is acceleration due to gravity and "h" is the displacement.


The work done by the man is -15.03J.
(b) <u>Calculating the force</u>:
Probably the man and the object are close to the exterior of the earth. If the rigidity required to maintained the object of consistent velocity interior the gravitational field of the earth is 
Thus the weight of the object is balanced by the force of the man's teeth on the object. That is
F = mg

F = 127.4N
The force exerted on the object is 127.4N.