They’re right that is the answer
5000 feet = 0.947 miles.
Speed= ?
Distance=o.947 miles
Time= 0.1 hours
Speed=distance/time
= 0.947/0.1
=9.47 miles per hour
Answer:
The primary reason of seeing the cracker burst and hearing the sound later is because the speed of sound and light. Speed of light is in the vicinity of 3*10^8m,/ sec while the speed of sound is at a distance of 332m/sec. It is similar to lightning that strikes before the sound.
hope this helped you
please mark as the brainliest (ㆁωㆁ)(ㆁωㆁ)
Answer:
20 m/s
Explanation:
Height (s)= 20m
acceleration (a) = 10 m/s^2
v=?
we know,
V^2= U^2 + 2as. (U is initial velocity)
or,. V^2 = 0 + 2 × 10 × 20
or, V^2 = 400
or,. V = 20 m/s
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