Answer:
14.36m/s
Explanation:
From the law of conservation of linear momentum
m1u1 + m2u2 = v(m1 + m2)
68×17 + 76×12= v(68+76)
1156+912 = 144v
2068 = 144v
v = 2068/144
=14.36 m/s
Effort force and Resistance force
Answer:
F = 3.20 N
Explanation:
Given:
Work done by child = 80.2 j
Distance that the car moves = 25.0 m
We need to find the force acting on the car.
Solution:
Using work done formula as.

Where:
W = Work done by any object.
F = Force (push or pull)
d = distance that the object moves.
Substitute
in work done formula.


F = 3.20 N
Therefore, force acting on the car F = 3.20 N
Answer:
Photoelectric-type alarms aim a light source into a sensing chamber at an angle away from the sensor. Smoke enters the chamber, reflecting light onto the light sensor; triggering the alarm.
Explanation:
nfpa.org is the website with theanswer
Part of the scientific process involves sharing your results with other scientists. To do this, we all need to use the same measurement system, which you'll learn about in this lesson.
Imagine you're trying to find out how much an elephant weighs. You're pretty sure it weighs a lot, but you don't know the exact number. So you ask your teacher, and she tells you an elephant weighs the same as three hippos.
Well that's nice to know, but how much does a hippopotamus weigh? Again, you ask your teacher, and she tells you a hippopotamus weighs the same as five alligators. That's a cool fact to know, but you still don't understand how much an elephant weighs because comparing elephants to alligators can be confusing.
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