7. PE=0.5×700n/m×0.9m^2
0.9^2=0.81m
0.5×700×0.81= 283.5J
8. 2000=0.5×(x)×1.5m^2
1.5^2= 0.25
0.25×0.5=0.125
2000=0.125 (x)
2000/0.125=x
x=16000 n/m
9. 4000=0.5 (375 n/m)×(x)^2
0.5×187.5 (x)
4000/187.5=21.3333333333
Answer:
Mass of a body is define as the total quantity of matter contained in it .
Density is the mass per unit volume in any object .
A physical properties is an any property that is measurable , whose value describe a state of a physical system
Answer: h = 0.30 m
Explanation:
A person jumping from height h would possess potential energy = m g h
which will convert completely into kinetic energy as person hits the ground. Now, the maximum energy absorbed by the person can be = 200 J
m = 67 kg
g = 9.8 m/s²
⇒ m g h = 200 J
⇒ h = 200 J / (67 kg × 9.8 m/s²) = 0.30 m
Hence, a person can land safely on both legs without breaking them from a height of 0.30 m only.
<span>The statement Today's Apple Mac computers run with the same internal hardware as the Windows-based PC is true. Mac computers are Windows-based PC because windows has a connection with apple because the idea of it came from one person.</span>
The amount of work which Sam does need to stop the boat is 784Joule if boat mass is 800kg and boat drift in 1.4m/sec.
We know that according to work-energy theorem, change in kinetic energy of the body from one speed to another is equivalent to amount of work done by all forces acting on the body.
So, here we can see that final speed of boat is =0m/sec since Sam need to stop it.
Initial speed of boat is 1.4m/sec.
Also, we know that kinetic energy is given by the below formula:
Kinetic energy=(1/2)mv²
where m is the mass of the body
and v is the speed of the body
Now, from work energy theorem, we get
=>W=(1/2)m
- (1/2)m
=>W=0-(1/2)×800×(1.4)²
=>W= - 400× 1.4 × 1.4
=>W = -400×1.96
=>W= -784Joule
Here negative sign denotes work has to done against the original motion of boat.
Hence, amount of work needs to be done by Sam is 784Joule.
To know more about work,visit here:
brainly.com/question/18094932
#SPJ4
