Answer:
a fossil of a footprint, trail, burrow, or other trace of an animal rather than of the animal itself.
Explanation:
Trace fossils are the indirect evidence of life in the past, such as the footprints, tracks, burrows, borings, and feces left behind by animals, rather than the preserved remains of the actual animal body itself.
Fossil is the naturally preserved remains of plants and animals which somehow get trapped in amber, hair, petrified wood, oil, coal, and DNA remnants.
Answer:
As the person moves down the zip wire, her increase in kinetic energy is less than her decrease in gravitational potential energy.
Explanation:
Work is done against the air resistance, causing thermal energy to transfer to the surroundings
Answer:
option (b)
Explanation:
According to the Pascal's law
F / A = f / a
Where, F is the force on ram, A be the area of ram, f be the force on plunger and a be the area of plunger.
Diameter of ram, D = 20 cm, R = 20 / 2 = 10 cm
A = π R^2 = π x 100 cm^2
F = 3 tons = 3000 kgf
diameter of plunger, d = 3 cm, r = 1.5 cm
a = π x 2.25 cm^2
Use Pascal's law
3000 / π x 100 = f / π x 2.25
f = 67.5 Kgf
Answer:
Impulse = 90
Resulting Velocity = 89
Explanation:
Use F * change in time = m * change in velocity.
For the first part of the question, the left side of the equation is the impulse. Plug it in.
60 * (3.0 - 0) = 90.
For the second half. we use all parts of the equation. I'm gonna use vf for the final velocity.
60 * (3.0 - 0) = 10 * (vf - 80). Simplify.
90 = 10vf - 800. Simplify again.
890 = 10vf. Divide to simplify and get the answer.
The resulting velocity is 89.
To solve this problem we will use the trigonometric concepts to find the distance h, which will allow us to find the speed of Jeff and that will finally be the variable that will indicate the total tension, since it is the variable of the centrifugal Force given in the vine at the lowest poing of the swing.
From the image:
When Jeff reaches his lowest point his potential energy is converted to kinetic energy
Tension in the string at the lowest point is sum of weight of Jeff and the his centripetal force
Therefore the tension in the vine at the lowest point of the swing is 842.49N
