Answer:
Explanation:
Frictional force acting on incline = μ mg cosθ
μ is coefficient of friction , m is mass of object , θ is incline
= .09 x m x 9.8 x cos 28
= .78 m
work done by friction
= frictional force x displacement
= - .78m x 100
= - 78m
Potential energy of sli at height
= mgh
= m x 9.8 x 100 sin 28
= 460.08 m
net energy at the base
= 460.08m - 78 m
= 382.08 m
This will be in the form of kinetic energy .
1/2 m v² = 382.08 m
.5 x v² = 382.08
v = 27.64 m/s
After that it travels on plane surface .
Let the distance travelled be d
work done by frictional force
= μ mg x d
= .09 x m x 9.8 x d
This will be equal to kinetic energy at the base
.09 x m x 9.8 x d = 382.08 m
d = 433.2 meter .
Answer:B=Negative C=Positive D=Positive
Explanation:objects that repel each other means they have the same polarity. objects that attract have the opposite polarity A is negatively charged if A and B repel then A and B are both negative. B is negatively charged if B and C attract then they have reverse polarity which makes C positively charged. C is positive if C and D repel then that means that C and D have the same polarity making D positively charged.
Answer:
student A
Explanation:
It's going the same value
To solve this exercise it is necessary to apply the equations concerning Work, both by general definition and by conservation of energy.
In other words, the work done by an object due to gravity is the equivalent to that defined by the potential energy equations, that is
Where,
m=mass
g=gravitational acceleration
Change in height
On the other hand we have that the work done by tension is defined by the conservation of kinetic and potential energy, that is to say
Where,
Change in Kinetic Energy
Change in Potential Energy
PART A) As defined by the work done by gravity would be given by,
Therefore the work done by gravity is 25.725kJ
PART B) The work done by the tension applies the energy conservation equation, that is to say
Replacing with our values,
Therefore the work done by tension is 25.9kJ