Answer:
inertia
Explanation:
While riding a skateboard, Nina ran into a rough patch of pavement, but she thought she could ride right over it. Instead, the skateboard stopped but Nina didn't. Her (Blank) kept her moving forward, so she fell off the skateboard.inertia
Answer:
A) v = 40 m / s, B) v_average = 20 m / s
Explanation:
For this exercise we will use the kinematics relations
A) the final velocity for t = 5 s and since the body starts from rest its initial velocity is zero
v = vo + a t
v = 0 + 8 5
v = 40 m / s
B) the average velocity can be found with the relation
v_average = vf + vo / 2
v-average = 0+ 40/2
v_average = 20 m / s
Answer:Bruce is knocked backwards at
14
m
s
.
Explanation:
This is a problem of momentum (
→
p
) conservation, where
→
p
=
m
→
v
and because momentum is always conserved, in a collision:
→
p
f
=
→
p
i
We are given that
m
1
=
45
k
g
,
v
1
=
2
m
s
,
m
2
=
90
k
g
, and
v
2
=
7
m
s
The momentum of Bruce (
m
1
) before the collision is given by
→
p
1
=
m
1
v
1
→
p
1
=
(
45
k
g
)
(
2
m
s
)
→
p
1
=
90
k
g
m
s
Similarly, the momentum of Biff (
m
2
) before the collision is given by
→
p
2
=
(
90
k
g
)
(
7
m
s
)
=
630
k
g
m
s
The total linear momentum before the collision is the sum of the momentums of each of the football players.
→
P
=
→
p
t
o
t
=
∑
→
p
→
P
i
=
→
p
1
+
→
p
2
→
P
i
=
90
k
g
m
s
+
630
k
g
m
s
=
720
k
g
m
s
Because momentum is conserved, we know that given a momentum of
720
k
g
m
s
before the collision, the momentum after the collision will also be
720
k
g
m
s
. We are given the final velocity of Biff (
v
2
=
1
m
s
) and asked to find the final velocity of Bruce.
→
P
f
=
→
p
1
f
+
→
p
2
f
→
P
f
=
m
1
v
1
f
+
m
2
v
2
f
Solve for
v
1
:
v
1
f
=
→
P
f
−
m
2
v
2
f
m
1
Using our known values:
v
1
f
=
720
k
g
m
s
−
(
90
k
g
)
(
1
m
s
)
45
k
g
v
1
f
=
14
m
s
∴
Bruce is knocked backwards at
14
m
s
.
Explanation:
<h3><u>Answer and explanation;</u></h3>
-Rate of reaction is the speed at which the reactants are converted to products.
-Rate of reactions depends on a number of factors which includes<u>;</u>
- <em><u>Concentration of reactants</u></em>;<u><em> increasing the concentration of reactants</em></u> increases the rate of reaction.
- <u><em>Temperature;</em></u><u><em> </em></u>An <u><em>increase in temperature results to an increased rate of reaction.</em></u> Increase in temperature increases the kinetic energy of molecules thus the collision per unit time also increases and hence the rate of reaction increases.
- <u><em>Decreasing the size of particles of solid reactants</em></u> also increases the rate of reaction. This is because smaller particles increases the surface area on which more collisions can occur thus a faster rate of reaction.
- <em>Adding a catalyst also increases the rate of reaction.</em> This is because catalysts lower the activation energy of reactants, minimum energy require by reactants for the reaction to take place. This thus increases the rate of reaction.
Answer:
1)m=89.01 g
2)V(max) = 97.3 cm/s
Explanation:
Given that
K= 15 N/m
The maximum amplitude ,A=7.5 cm = 0.075 m
Given that 31 oscillations in 15 seconds ,this means that frequency f
f=\dfrac{31}{15}
f=2.066 Hz
lets take mass of the ball = m kg
m=0.08901 kg
m=89.01 g
The maximum speed
V(max)= ω x A
ω = 2π f= 2 x π x 2.066 = 12.98 rad/s
V(max) = 12.98 x 0.075 =0.973 m/s
V(max) = 97.3 cm/s
