Answer:
ΔU = -70 J
Explanation:
ΔU = Q − W
where ΔU is the change in internal energy,
Q is the heat absorbed by the system,
and W is the work done by the system (on the surroundings).
30 J of thermal energy is released, so Q = -30 J.
40 J of work is done by the system, so W = 40 J.
Therefore, the change in internal energy is:
ΔU = -30 J − 40 J
ΔU = -70 J
Explanation:
Let's solve the problem by using conservation of momentum:
m1 u1 + m2 u2 = m1 v1 + m2 v2
where:
m1 = 3.5 g is the mass of the blue marble
m2= 1.2 g is the mass of the red marble
u1 = 15 cm/s is the initial velocity of the blue marble
u2 = 3.5 cm/s is the initial velocity of the red marble
v1 = 5.5 cm/s is the final velocity of the blue marble
We can find the final velocity of the red marble by re-arranging the equation and solving for v2 :
v2 = 1/m²(m1 u1 + m2 u2 - m1 v1)=
=1/1.2(3.5×15+1.2×3.5−3.5×5.5 )=31cm/s
Answer:
the current is 3.5 A
Explanation:
The computation of the current is shown below:
As we know that
Current [A] = Electrical power [W] ÷ Potential difference [V]
Now convert KW TO W = × 1000
So, the current is
= 800W ÷ 230V
= 3.5 A
Hence, the current is 3.5 A
At the highest point in its trajectory, the ball's acceleration is zero but its velocity is not zero.
<h3>What's the velocity of the ball at the highest point of the trajectory?</h3>
- At the highest point, the ball doesn't go more high. So its vertical velocity is zero.
- However, the ball moves horizontal, so its horizontal component of velocity is non - zero i.e. u×cosθ.
- u= initial velocity, θ= angle of projection
<h3>What's the acceleration of the ball at the highest point of projectile?</h3>
- During the whole projectile motion, the earth exerts the gravitational force with a acceleration of gravity along vertical direction.
- But as there's no acceleration along vertical direction, so the acceleration along vertical direction is zero.
Thus, we can conclude that the acceleration is zero and velocity is non-zero at the highest point projectile motion.
Disclaimer: The question was given incomplete on the portal. Here is the complete question.
Question: Player kicks a soccer ball in a high arc toward the opponent's goal. At the highest point in its trajectory
A- neither the ball's velocity nor its acceleration are zero.
B- the ball's acceleration points upward.
C- the ball's acceleration is zero but its velocity is not zero.
D- the ball's velocity points downward.
Learn more about the projectile motion here:
brainly.com/question/24216590
#SPJ1
