A block of mass 5 kg is place on a table top.it is attached to a mass piece of 2kg by a light string that passes over a frictionless pulley.the table top exerts a frictional force of 7 N on the block.
calculate the tension in the string.
The volume of gas îs 76cm at 27c and 800mm mercury pressure.what is the volume at s.t.p.?
FR=ma
7=(5+2)a
7=(7)a
7÷7=7a÷7
a=1m.s^-2
To calculate the tension in the string, we can use Newton's second law of motion. The tension in the string can be determined by analyzing the forces acting on the block.
First, let's list the forces acting on the block:
1. Weight force (gravity) acting vertically downward on the block, equal to the mass of the block multiplied by the acceleration due to gravity (9.8 m/s^2).
2. Tension force in the string, pulling upward on the block.
3. Frictional force acting horizontally on the block, exerted by the table top.
The block is in equilibrium, which means the net force acting on it is zero. Since the vertical forces are balanced (the weight force is canceled by the tension force), we only need to consider the horizontal forces.
Since the block is not moving vertically, the tension force in the string (pulling upward on the block) is equal in magnitude to the weight force (pulling downward on the block). So, we can calculate the weight force:
Weight force = mass of the block * acceleration due to gravity
Weight force = 5 kg * 9.8 m/s^2
Weight force = 49 N
Now, let's analyze the horizontal forces. The only horizontal force acting on the block is the frictional force exerted by the table top. According to Newton's second law, the net force acting on the block horizontally is equal to the product of the mass of the block and its acceleration:
Net force = mass of the block * acceleration
Frictional force - Tension force = mass of the block * acceleration
Substituting the given values:
7 N - Tension force = 5 kg * acceleration
Since the block is at rest (not moving horizontally), its acceleration is zero. Therefore, the equation becomes:
7 N - Tension force = 0
Rearranging the equation, we can solve for the tension force:
Tension force = 7 N
Hence, the tension force in the string is 7 N.