In exothermic reactions, heat and light are released to the surrounding environment. On the other hand, in an endothermic reaction, heat is required and therefore it can be considered as a reactant.
- In exothermic reactions, light and heat are released into the environment (Option D).
- Exothermic reactions release energy in the form of heat or light.
- Combustion reactions are generally exothermic reactions.
- After an exothermic reaction takes place it is possible to observe that the energy of the products of the reaction is lesser than the energy of the reactants.
- The energy released in exothermic reactions is evidenced by the increase in temperature of the reaction.
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Answer:
3.28 m
3.28 s
Explanation:
We can adopt a system of reference with an axis along the incline, the origin being at the position of the girl and the positive X axis going up slope.
Then we know that the ball is subject to a constant acceleration of 0.25*g (2.45 m/s^2) pointing down slope. Since the acceleration is constant we can use the equation for constant acceleration:
X(t) = X0 + V0 * t + 1/2 * a * t^2
X0 = 0
V0 = 4 m/s
a = -2.45 m/s^2 (because the acceleration is down slope)
Then:
X(t) = 4*t - 1.22*t^2
And the equation for speed is:
V(t) = V0 + a * t
V(t) = 4 - 2.45 * t
If we equate this to zero we can find the moment where it stops and begins rolling down, that will be the highest point:
0 = 4 - 2.45 * t
4 = 2.45 * t
t = 1.63 s
Replacing that time on the position equation:
X(1.63) = 4 * 1.63 - 1.22 * 1.63^2 = 3.28 m
To find the time it will take to return we equate the position equation to zero:
0 = 4 * t - 1.22 * t^2
Since this is a quadratic equation it will have to answers, one will be the moment the ball was released (t = 0), the other will eb the moment when it returns:
0 = t * (4 - 1.22*t)
t1 = 0
0 = 4 - 1.22*t2
1.22 * t2 = 4
t2 = 3.28 s
Answer:
Explanation:
Learn vocabulary, terms, and more with flashcards, games, and other study tools. ... A jogger sprints 100 m in 13 seconds. What is her average speed? 7.7 m/s ... Kathryn swam 5 complete laps of a 50 m pool. ... stands still for 4 seconds, then continues to walk for 8 meters moving away from the starting point in 6 seconds.
The rotational speed of the person is 0.4 rad/s.
<h3>
Rotational speed (rad/s)</h3>
The rotational speed of the person in radian per second is calculated as follows;
v = ωr
where;
- v is linear speed in m/s
- r is radius in meters
- ω is speed in rad/s
ω = v/r
ω = 2/5
ω = 0.4 rad/s
Thus, the rotational speed of the person is 0.4 rad/s.
Learn more about rotational speed here: brainly.com/question/6860269
Answer:
= 351.84 J
Explanation:
Using the conservation of energy K:
so:
where m is the mass, v the initial velocity, is the kinetic energy of the mass as it clears the fence, g the gravity and h the altitude.
Then, replacing values, we get:
solving for :
= 351.84 J
