Answer: Speed = 4 m/s
Explanation:
The parameters given are
Mass M = 60 kg
Height h = 0.8 m
Acceleration due to gravity g= 10 m/s2
Before the man jumps, he will be experiencing potential energy at the top of the table.
P.E = mgh
Substitute all the parameters into the formula
P.E = 60 × 9.8 × 0.8
P.E = 470.4 J
As he jumped from the table and hit the ground, the whole P.E will be converted to kinetic energy according to conservative of energy.
When hitting the ground,
K.E = P.E
Where K.E = 1/2mv^2
Substitute m and 470.4 into the formula
470.4 = 1/2 × 60 × V^2
V^2 = 470.4/30
V^2 = 15.68
V = square root (15.68)
V = 3.959 m/s
Therefore, the speed of the man when hitting the ground is approximately 4 m/s
energy associate with position or shape
Answer:
A: used has four times the tensile strength of steel and the timber frame, incorporating
Explanation:
Option A is correct because it conveys the correct message intended by the statement and has no grammatical errors.
Option B is wrong because to say "has four times the tensile strength of steel has" is just grammatically and idiomatically wrong as has is used twice in the sentence.
Option C is wrong because the statement that has to do with the flexibility of the timber's frame is more like a separate fact and does not fall under the scope of trying to further explain a fact.
Option D is wrong because it has the same problem in Option C. The comma that is placed after "steel" breaks the sentence and hence does not provide a good understanding of why the building can withstand earthquakes.
Option E is grammatically wrong for using does in the sentence "has four times the tensile strength steel does"
Answer:
stop, drop and roll.
Explanation:
This is because rolling on the ground can help put out the fire by depriving it of oxygen.