The answer should be C. Encourage his daughter to make friends with the new boy.
Hope this helps and have a happy new year
A. power plants burn coal. A fossil-fuel power plant is one that burns fossil fuels such as coal, natural gas or petroleum (oil) to produce electricity.
b. Fossil fuels are called so because they have been derived from fossils, which were formed millions of years ago during the time of the dinosaurs. They are fossilized organic remains that over millions of years have been converted to oil, gas, and coal.
C. they are generally classified as non-renewable resources because they take millions of years to form and known viable reserves are being depleted much faster than new ones are generated.
5.
a. Gravitational potential energy and work done
If an object is lifted, work is done against the force of gravity.
When work is done energy is transferred to the object and it gains gravitational potential energy.
If the object falls from that height, the same amount of work would have to be done by the force of gravity to bring it back to the Earth’s surface.
If an object at a certain height has 2000 J of gravitational potential energy, we can say that:
2000 J of work has been done in getting the object to that height from the ground
and
2000 J of work would have to be done to bring it back to the ground.
Answer:
Explanation:
The equation for acceleration is
where vf is the final velocity and v0 is the initial velocity. Filling in:
so
a = 2.5 m/s/s
Answer:
44.3 m/s
Explanation:
a) Draw a free body diagram of the mass M. There are three forces:
Weight force mg pulling down,
Normal force N pushing perpendicular to the ramp,
and tension force T pulling parallel up the ramp.
Sum of forces in the parallel direction:
∑F = ma
T − Mg sin 30° = 0
T = Mg sin 30°
T = Mg / 2
Draw a free body diagram of the hanging mass m. There are two forces:
Weight force mg pulling down,
and tension force T pulling up.
Sum of forces in the vertical direction:
∑F = ma
T − mg = 0
T = mg
Substitute:
mg = Mg / 2
m = M / 2
M = 2m
b) Velocity of a standing wave in a string is:
v = √(T / μ)
T = mg, and m = 5 kg, so T = (5 kg) (9.8 m/s²) = 49 N. Therefore:
v = √(49 N / 0.025 kg/m)
v = 44.3 m/s
