Answer:
-35 m/s
Explanation:
Momentum is conserved.
Momentum before firing = momentum after firing
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
Before the bullet is fired, the bullet and rifle have no velocity, so u₁ and u₂ are 0.
0 = m₁v₁ + m₂v₂
Given m₁ = 0.7 kg, v₁ = 350 m/s, and m₂ = 7 kg:
0 = (0.7 kg) (350 m/s) + (7 kg) v
v = -35 m/s
The rifle recoils at 35 m/s in the opposite direction.
Answer:
1.2 ft/s or 72 ft/min
Explanation:
To solve this problem, we can use the relationship between the angular and linear speed for this particular movement (rotation). As the speed of the current is tangent to the trajectory of the wheel we can define as follows:
The speed of the current is 72 ft/min
According to the second law of motion, force is equal to the product of mass and acceleration. This means force is proportional to mass. Hence when mass increases, it is understood that force should increase as well. In this case,the answer to this problem is A.
Answer:
See the answer below
Explanation:
Newton's third law states that for every action, there will always be an opposing reaction of equal magnitude to the action.
<em>Hence, the wall will exert an equal opposing force to the head and the roommate will feel this opposing force as pains and/or headache. </em>
