Answer:
a. F = 245 Newton.
b. Workdone = 392 Joules.
c. Power = 196 Watts
Explanation:
Given the following data;
Mass = 25kg
Distance = 1.6m
Time = 2secs
a. To find the force needed to lift the mass (in N );
Force = mass * acceleration
We know that acceleration due to gravity is equal to 9.8
F = 25*9.8
F = 245N
b. To find the work done by the student (in J);
Workdone = force * distance
Workdone = 245 * 1.6
Workdone = 392 Joules.
c. To find the power exerted by the student (in W);
Power = workdone/time
Power = 392/2
Power = 196 Watts.
Negative - when the motorcycle displacement has a component in the opposite direction of the given force, that force is doing negative work on the motorcycle.
To solve this problem it is necessary to apply the conservation equations of the moment for an inelastic impact or collision. In turn, it is necessary to apply the equations related to the conservation of potential energy and kinetic energy.
Mathematically this definition can be expressed as

Where,
Initial velocity of each object
Mass of each object
Final velocity
Our values are given as

Replacing we can find the value of the final velocity, that is


From the definition of the equations of simple harmonic motion the potential energy of compression and equilibrium must be subject to

Since there is no kinetic energy due to the zero speed in compression, nor potential energy at the time of equilibrium at the end, we will have to

Re-arrange to find A



Finally, the period can be calculated through the relationship between the spring constant and the total mass, that is,



Answer:
Its acceleration is positive
Explanation:
As the car is moving in the negative x-direction than after applying brake then there will be a decrease in the acceleration but in the opposite direction.
As decreasing acceleration consider to be negative but the car is moving in negative direction which means increasing acceleration is negative by sign convention but by applying brake acceleration decrease but in opposite direction than it will give positive value of acceleration.
All three are forms of renewable energy.
Wind turbines utilize the wind to generate power, hydroelectric dams also do the same (although most states have stopped using them since they're bad for the environment)
Ethanol, a substitute for gasoline, comes from corn, which can be grown in farms throughout America.