How do catalysts speed up reactions ?
by reducing the amount of energy required for the reaction to occur. other factors such as <span>catalysts' ability to speed a process are temperature, concentration </span>
Answer:
y = 54.9 m
Explanation:
For this exercise we can use the relationship between the work of the friction force and mechanical energy.
Let's look for work
W = -fr d
The negative sign is because Lafourcade rubs always opposes the movement
On the inclined part, of Newton's second law
Y Axis
N - W cos θ = 0
The equation for the force of friction is
fr = μ N
fr = μ mg cos θ
We replace at work
W = - μ m g cos θ d
Mechanical energy in the lower part of the embankment
Em₀ = K = ½ m v²
The mechanical energy in the highest part, where it stopped
= U = m g y
W = ΔEm = - Em₀
- μ m g d cos θ = m g y - ½ m v²
Distance d and height (y) are related by trigonometry
sin θ = y / d
y = d sin θ
- μ m g d cos θ = m g d sin θ - ½ m v²
We calculate the distance traveled
d (g syn θ + μ g cos θ) = ½ v²
d = v²/2 g (sintea + myy cos tee)
d = 9.8 12.6 2/2 9.8 (sin16 + 0.128 cos 16)
d = 1555.85 /7.8145
d = 199.1 m
Let's use trigonometry to find the height
sin 16 = y / d
y = d sin 16
y = 199.1 sin 16
y = 54.9 m
t = time of contact of hammer with the nail = 0.4 sec
I = impulse exerted by the hammer on the nail = 32 N s
F = force applied by the hammer on the nail
we know that , impulse is given as
I = F t where I = impulse , F = force , t = time
hence the impulse of hammer on nail is given as
I = F t
inserting the values
32 Ns = F (0.4 sec)
F = 32/0.4
F = 80 N
hence the force exerted by the hammer comes out to be 80 N
As per the information given, there's most probability that the air over the lake will reach its highest temperature later in the day and will stay warm longer than air over the ground.
Answer: Option A
<u>Explanation:</u>
According to the concepts of the specific heats capacity of matter; it is observed that water possesses high specific heats capacity as compared to metals and other solids. Water takes much more time to absorb heat from the atmosphere and the same way takes time while releasing it into the atmosphere.
Whereas, solids and most metals have the tendency to quickly absorb and release the heat. Hence, it seems that the student may observe the rise in temperature for the air over the water lake later in the day which will stay warm longer than the air over the ground.
