Answer:
The average force exerted on the man by the ground therefore is 153.319.53 N
Explanation:
Given the following information
Mass of man, m = 75 kg
height of fall, h = 0.48 cm
velocity just before landing, v = 4.43 m/s
We therefore have
The work required to break the fall is equal to the kinetic energy of motion, just before touching the ground
Work done = Energy to absorb Kinetic Energy KE = 0.5·m·v²= F·h
Where:
F = Force required to break the fall
Therefore the force, F = (0.5·m·v² )/h
= 0.5×75 kg ×(4.43 m/s)²/(0.0048 m) = 153319.53 N
The average force exerted on him by the ground is therefore
= 153319.53 N.
Answer:
17. h = l − l cos θ
18. 1.40 m
Explanation:
Let's call d the height of the triangle. We can then say:
h = l − d
Using trig, we can write d in terms of l and θ:
d = l cos θ
h = l − l cos θ
If l = 6 m and l cos θ = 40°:
h = 6 − 6 cos 40
h ≈ 1.40
Answer:
The object must be placed just ahead of focus towards the lens.
Explanation:
As we know that a magnifying glass is a convex lens and for the convex lens and for a convex lens we get the image virtual, erect and magnified only when it is placed between the optical center and the focus of the lens.
In that range when the object is nearest to the focus of the lens it has the maximum size.
So it can be possible if the object is placed at 9.98 cm from the optical center.
The largest image is formed at infinity when the object is placed at focus but it is not visible to the normal eyes.
Answer:
The given statement is correct.
When the light becomes brighter then the electron emitted per second increases.
when light is incident on the metal it delivers energy in the form of small energy packets.
these small energy packets is known as photons.
More the intensity of light more the photon will be emitted.
Electron gain kinetic energy after absorbing energy from the photon.
Explanation:
An element contains just one type of atom. A compound contains two or more different atoms joined together. A mixture contains two or more different substances that are only physically joined together, not chemically. A mixture can contain both elements and compounds.
