The trip time taken by the box is 1.5 sec.
Explanation:
Given:
distance(d) = 30 m
Velocity(v) = 20 m/s
By using formula:
Velocity = ![\frac{distance}{time}](https://tex.z-dn.net/?f=%5Cfrac%7Bdistance%7D%7Btime%7D)
or, 20 = ![\frac{30 }{time}](https://tex.z-dn.net/?f=%5Cfrac%7B30%20%7D%7Btime%7D)
or, time(t) = ![\frac{30}{20}](https://tex.z-dn.net/?f=%5Cfrac%7B30%7D%7B20%7D)
∴ time (t) = 1.5 sec
Hence the the block took 1.5 sec to slide 30 m.
Daniddmelo says it right there, don't know why he got reported.
The potential energy (PE) is mass x height x gravity. So it would be 25 kg x 4 m x 9.8 = 980 joules. The child starts out with 980 joules of potential energy. The kinetic energy (KE) is (1/2) x mass x velocity squared. KE = (1/2) x 25 kg x 5 m/s2 = 312.5 joules. So he ends with 312.5 joules of kinetic energy. The Energy lost to friction = PE - KE. 980- 312.5 = 667.5 joules of energy lost to friction.
Please don't just copy and paste, and thank you Dan cause you practically did it I just... elaborated more? I dunno.
18:4 can be written as
9:2<---- when reduced
Answer:
63.57 kg
Explanation:
weight = 140 lbs
Let the mass is m.
1 lbs = 4.45 N
The weight of an object is defined as the force with which our earth attracts the body towards its centre.
Weight is the product of mass of the body and the acceleration due to gravity of that planet.
W = m x g
On earth surface g = 9.8 m/s^2
Now convert lbs in newton
So, 140 lbs = 140 x 4.45 = 623 N
So, m x 9.8 = 623
m = 63.57 kg
Thus, the mass is 63.57 kg.