ElloNY1 ZINDA HERE xDWHAT IS MOLE ??
1 answer:
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a) The initial speed of the clay is 30 m/s
b) The final velocity of the block increases (40 m/s)
Explanation:
a)
We can solve this problem by using the law of conservation of momentum. In fact, in absence of external forces (=no friction), the total momentum of the clay + block system is conserved before and after the collision. Therefore, we can write:
where:
is the mass of the clay
is the initial velocity of the clay
is the mass of the wood block
is the initial velocity of the wood block (at rest)
is the final combined velocity of the clay+block after the collision
Re-arranging the equation, we can find , the speed at which the clay was tossed:
b)
In this second case, the clay is replaced by a bouncy ball, which rebounds back after the collision, instead of sticking with the block.
In this second case, the law of conservation of momentum becomes:
where
is the mass of the ball
is the initial velocity of the ball
is the mass of the wood block
is the initial velocity of the wood block (at rest)
is the velocity of the bouncing ball after the collision (negative because it goes backward)
is the velocity of the block after the collision
Solving for , we find the final velocity of the block:
As we can see, the final velocity of the block has increased. The reason for that is that, as the ball bounces back, part of the total momentum is "carried away" by the ball in the backward direction, and since the total momentum must remain constant, this means that the momentum carried by the block in the forward direction must be larger than the previous situation.
Learn more about conservation of momentum:
#LearnwithBrainly
<u>Answer</u>:
(a) magnitude of F = 797 N
(b)the total work done W = 0
(c)work done by the gravitational force = -1.55 kJ
(d)the work done by the pull = 0
(e) work your force F does on the crate = 1.55 kJ
<u>Explanation</u>:
<u>Given</u>:
Mass of the crate, m = 220 kg
Length of the rope, L = 14.0m
Distance, d = 4.00m
<u>(a) What is the magnitude of F when the crate is in this final position</u>
Let us first determine vertical angle as follows
=>
=> =
Now substituting thje values
=> =
=>
=>
=>
Now the tension in the string resolve into components
The vertical component supports the weight
=>
=>
=>
=>
=>
=>T =2391N
Therefore the horizontal force
F = 797 N
b) The total work done on it
As there is no change in Kinetic energy
The total work done W = 0
<u>c) The work done by the gravitational force on the crate</u>
The work done by gravity
Wg = Fs.d = - mgh
Wg = - mgL ( 1 - Cosθ )
Substituting the values
=
=
=
=
=
= -1552.55 J
The work done by gravity = -1.55 kJ
<u>d) the work done by the pull on the crate from the rope</u>
Since the pull is perpendicular to the direction of motion,
The work done = 0
e)Find the work your force F does on the crate.
Work done by the Force on the crate
WF = - Wg
WF = -(-1.55)
WF = 1.55 kJ
<u>(f) Why is the work of your force not equal to the product of the horizontal displacement and the answer to (a)</u>
Here the work done by force is not equal to F*d
and it is equal to product of the cos angle and F*d
So, it is not equal to the product of the horizontal displacement and the answer to (a)