3] A snowball picks up speed as it rolls down the mountain.
Explanation:
Newton's second law states that:
[tex]F=ma[/tex]
where
F is the net force acting on an object
m is the mass of the object
a is the acceleration of the object
When the net force acting on the object is zero, we say that the object is acted upon balanced forces; when the net force is non-zero, we say that unbalanced forces are acting on the object. From the formula, we see that when unbalanced forces are acting on the object, the object has an acceleration different from zero: this also means that the velocity of the object is changing.
So, we can say that if there are unbalanced forces, then the object's velocity is changing. Among the choices given, we see that velocity is changing only in options 3) (the snowball is speeding up, so it has an acceleration), while in all other cases the velocity is constant. Therefore, option 3) is the correct one.
Option (C) is correct. A snowball pick up speed as it rolls down the mountain is an example of unbalanced force.
Further Explanation:
A body is said to be acted upon by an unbalanced force when there is acceleration in the body during its motion. An accelerating body is said to be acted upon by an unbalanced force by the Newton’s second law of motion.
Newton’s second law of motion states thatthe force acting upon a body under acceleration is given as the product of mass and its acceleration. It can be expressed mathematically as:
[tex]F = ma[/tex]
As given in first option, a dog running at a constant velocity. It means that the motion of the dog is not accelerating. If a body has zero acceleration, then there is no unbalanced force acting on the body.
In the second and the fourth option, there is no motion of the body and if there is no disturbance ion the state of rest or motion of the body, the body is not under the action of unbalanced force.
In third option, the speed of the snow ball increases as it falls down the mountain. It means that the motion of the snow ball is accelerated motion and therefore, the snowball is acted upon by some unbalanced force
Thus, Option (C) is correct. A snowball pick up speed as it rolls down the mountain is an example of unbalanced force.
Learn More:
1.A 30.0-kg box is being pulled across a carpeted floor by a horizontal forcehttps://brainly.com/question/7031524
2.Choose the 200 kg refrigerator. Set the applied force to 400 n https://brainly.com/question/4033012
3.Which of the following is not a component of a lever https://brainly.com/question/1073452
Answer Details:
Grade: High School
Subject: Physics
Chapter: Force
Keywords: Unbalanced force, example, acceleration, newton’s law, second law, coffee cup, original spot, snowball, runs down mountain, constant velocity, net force.
