The first thing you should know to solve this problem is the conversion of pounds to kilograms:
1lb = 0.45 Kg
We can solve this problem by a simple rule of three
1lb ---> 0.45Kg
125lb ---> x
Clearing x we have:
x = ((125) / (1)) * (0.45) = 56.25 Kg.
Answer
her mass expressed in kilograms is 56.25 Kg.
Answer:
Explanation:
Speed of car =22.5miles/hr
U=22.5miles/hour
Applied brake and come to rest
Final velocity, =0
t, =2sec
Given that,
Speed=distance /time
Then,
Distance, =speed, ×time
Converting mile/hour to m/s
Given that
Use: 1 mile= 1600 m, 1 h= 3600s
22.5miles/hour × 1600m/mile × 1hour/3600s
Therefore, 22.5mile/hour=10m/s
Using speed =10m/s
Distance =speed ×time
Distance=10×2
Distance, =20m
The distance travelled before coming to rest is 20m.
Given:
Mass of the rail road car, m = 2 kg
velocity of the three cars coupled system, v' = 1.20 m/s
velocity of first car,
= 3 m/s
Solution:
a) Momentum of a body of mass 'm' and velocity 'v' is given by:
p = mv
Now for the coupled system according to law of conservation of momentum, total momentum of a system before and after collision remain conserved:
(1)
where,
= velocity of the first car
= velocity of the 2 coupled cars after collision
Now, from eqn (1)


v' = 1.80 m/s
Therefore, the velocity of the combined car system after collision is 1.80 m/s
Answer:
The value of 2.2 radians in degree is 126.11°.
Explanation:
Given that,
Angle = 2.2 radians
We need to calculate the value in degrees
We know that,



Hence, The value of 2.2 radians in degree is 126.11°.
Power is the rate work done given by dividing work done by unit time. It is measured in watts equivalent to J/s.
In this case the force by the student is mg = 490 N (taking g as 9.8m/s²)
Work done is given by force × distance,
Therefore, Power =(force × distance)/ time, but velocity/speed =distance/time
Thus, Power = force × speed/velocity
= 490 N × 1.25
= 612.5 J/S (Watts)
Hence, power will be 612.5 Watts.