(a) The minimum force F he must exert to get the block moving is 38.9 N.
(b) The acceleration of the block is 0.79 m/s².
<h3>
Minimum force to be applied </h3>
The minimum force F he must exert to get the block moving is calculated as follows;
Fcosθ = μ(s)Fₙ
Fcosθ = μ(s)mg
where;
- μ(s) is coefficient of static friction
- m is mass of the block
- g is acceleration due to gravity
F = [0.1(36)(9.8)] / [(cos(25)]
F = 38.9 N
<h3>Acceleration of the block</h3>
F(net) = 38.9 - (0.03 x 36 x 9.8) = 28.32
a = F(net)/m
a = 28.32/36
a = 0.79 m/s²
Thus, the minimum force F he must exert to get the block moving is 38.9 N.
The acceleration of the block is 0.79 m/s².
Learn more about minimum force here: brainly.com/question/14353320
#SPJ1
Answer:
Motion with constant velocity of magnitude 1 m/s (uniform motion) for 4 seconds in a positive direction and then for 2 seconds uniform motion with constant velocity of magnitude 3 m/s in reverse direction .
Explanation:
The graph shows a constant velocity of 1 m/s for 4 seconds in the positive direction. After that, between 4 seconds and 6 seconds, the object reverses its motion with constant velocity of magnitude 3m/s.
Two neutral objects will not have any electric force of attraction or repulsion between them.
<h3>What is the condition for the electric force between two objects?</h3>
As we know from the electrostatics that whenever there are two charges having a positive charge on one and a negative on the other will attract each other
similarly, if they are having like charges which are both of them having positive or both of them having a negative charge then there will be a force of repulsion between them.
But if both of them or even one of them is neutral then there will not be any electric force between them.
Thus neutral objects will not have any electric force of attraction or repulsion between them.
To know more about the nature of charged particles follow
brainly.com/question/22492496
Answer:
No. of Neutrons = 3
Explanation:
The atomic number of Lithium is given as 3 in the symbol while the mass number is given as 5.941 which is approximately equal to 6.
Mass Number = No. of Protons + No. of Neutrons = 6
Atomic Number = Number of Electrons = No. of Protons = 3
Therefore,
Mass Number - Atomic Number = (No. of Protons + No. of Neutrons) - No. of Protons
Mass Number - Atomic Number = No. of Neutrons
No. of Neutrons = 6 - 3
<u>No. of Neutrons = 3 </u>
Answer:
Option ( B ) is correct .
Explanation:
To lift a heavy weight , inclined plane is used . Use of inclined plane , makes the task easier because instead of force mg , force mg sinθ is to be used which is less than mg . Here θ is inclination of inclined plane.
If h be the height by which weight is to be lifted
potential energy acquired by weight = mgh
work done by force mg sinθ = mgsinθ x d where d is displacement required .
mg sinθ x d = mgh ( work done by force = potential energy stored in luggage )
d = h / sinθ
d will be more than h
Hence inclined plane increases the distance to be covered by force applied though it decreases the force itself.
Hence option ( B ) is correct .
