Answer:
-26 m/s (backward)
Explanation:
We can solve this problem by using the law of conservation of momentum.
In fact, the total momentum momentum of the cannon + ball system must be conserved before and after the explosion.
Before the explosion, they are both at rest, so the total momentum is zero:
p = 0
After the explosion, the total momentum is:
where
M = 1.5 kg is the mass of the cannon
m = 0.52 kg is the mass of the ball
v = +75 m/s is the velocity of the ball
V is the velocity of the cannon
Since the momentum is conserved, we can equate the two expressions:
And solving, we find V:
where the negative sign means the direction is opposite to that of the ball.
Mg magnesium becuase one period down and one group to the side
Answer:
225 rpm
Explanation:
The angular acceleration of the fan is given by:
where
is the final angular speed
is the initial angular speed
is the time interval
For the fan in this problem,
Substituting,
Now we can find the angular speed of the fan at the end of the 5th second, so after t = 5 s. It is given by:
where
Substituting,
Answer:
B
Explanation:
Angular speed=velocity/radius
5/0.85=5.9
Answer:
1 m = 100 cm....so 2.5 m = (2.5 * 100) = 250 cm
a = 1st shelf
b = 2nd
c = 3rd
d = 4th
a + b + c + d = 250
b = 2a + 18
c = a - 12
d = a + 4
a + (2a + 18) + (a - 12) + (a + 4) = 250
5a + 10 = 250
5a = 250 - 10
5a = 240
a = 240/5
a = 48 cm <== 1st shelf
b = 2a + 18 = 2(48) + 18 = 114 cm <== 2nd shelf
c = a - 12 = 48 - 12 = 36 cm <== 3rd shelf
d = a + 4 = 48 + 4 = 52 cm <== 4th shelf
so 2nd shelf is 114 cm
