Answer:
F = 30 N Directed up
Explanation:
We can solve this problem using the momentum and momentum relationship.
I = ΔP
I = ∫ F dt
As we are asked for the average force, that leaves the integral, giving
I = F t
F t = m 
- m v₀
F = m (-v₀) / t
Note that, if you define the upward positive direction, the initial velocity is negative
Let's calculate
F = 0.15 (3.5 - (-6.5)) / 0.050
F = 30 N
Directed up
Answer:
The force of friction is a necessary force which helps us to walk on ground. The friction is generated between the shoes and the road. We press the ground and as a reaction the ground pushes us forward. The force of friction between sole and ground provides the necessary grip which pushes us forward
Explanation:
Don't copy word for word if your sending as paragraph answer
Answer: C. 8.0 m west
Explanation: The arrows are going 15 m west and 7.0 m east. 7 meters of the west will cancel out because 15-7=8. Subtract the smaller number from the bigger number, which is west minus east. The answer will be 8.0 m west.
The answer to this question is B, Reacts with sunlight.
The 2 main properties of substances are their physical properties and chemical properties.
Physical properties are some observable/measurable characteristics, such as their color, mass, state, melting point, conductivity etc.
Meanwhile, for chemical properties, they're about how the substance reacts with other substances, such as metals react with acid to form hydrogen. And by the word "react", it means there's no way turn the reaction product back to the original substance without using chemical methods such as heating or electrolysis.
Therefore, all the choices above are physical properties of hydrogen peroxide except for B, as it is the only choice that relates to the substance reacting to another substance.
Answer: The softer barrier is the better option
Explanation:
1) When is a car is moving at a certain speed, it has a certain amount of momentum (p=mv). A collision against a barrier would cause its momentum to decrease to 0. A change in momentum is Impulse
2) The formula for Impulse: J = f * Δt
J is Impulse
f is the force applied during the time Δt
A tough barrier would produce a smaller Δt, which means more force is applied on the car. (J is always constant)
A softer barrier would apply less force on the car, which means Δt is large.
Answer: The softer barrier is the better option
