Answer:
Magnitude of the Frictional force = (mv₀²)/2x₁
Explanation:
For the frictional force to stop the box, it has to produce the deceleration of the box; thereby being the opposing force to the box's motion.
According to Newton's first law of motion
Frictional force = (mass of the box) × (deceleration experienced by the box)
Let the mass of the box be m
Then,
Frictional force = ma
Then we can obtain the deceleration using the equations of motion
v² = u² + 2ax
u = Initial velocity = v₀ m/s
v = Final velocity = 0 m/s (since the box comes to rest at the end)
x = horizontal distance covered = (x₁ - x₀) = x₁ (since x₀ = 0)
a = ?
v² = u² + 2ax
0 = (v₀)² + 2ax₁
2ax₁ = - v₀²
a = - (v₀²)/(2x₁) (minus sign, because it's a deceleration)
Magnitude of the Frictional force = ma = (mv₀²)/2x₁
Answer:
c. Time period remains the same in all.
Explanation:
In order to answer this question, we need to analyze the parameters, upon which the time period of a pendulum depends. We know that the time of a pendulum is given by the following formula:
T = 2π√(L/g)
where,
T = Time period
L = Length of pendulum
g = acceleration due to gravity
The formula clearly shows that the time period of the pendulum depends only upon the length of pendulum and value of g. And the time period of a pendulum does not depend upon the mass of the bob. Hence, the time period for each of the three pendulums will remain same. So, the correct option will be:
<u>c. Time period remains the same in all.</u>
ur answer is A or also known as
When you push a child on a swing, you are doing work on the child because you are pushing against the force of gravity
hope this helps :)
Answer:
1500000 Pa
Explanation:
The formula for pressure is force per unit area.
P=F/A where F is force and A is area
Given that ;
F= mass * acceleration due to gravity
F= 60 * 9.81 = 588.6 = 589 N
A= area = 4cm² = 0.0004 m²
P= F/A = 589 / 0.0004
P= 1471500
P=1500000 Pa
Answer:
W = -1844.513 J
Explanation:
GIVEN DATA:
mass of spider man is m 74 kg
vertical displacement if spider is 11 m
final displacement = 11 cos 60.6 = - 6.753 m
change in displacement is = -6.753 - (-11) = 4.25 m
gravity force act on spiderman is f = mg = 74 × 9.8 = 725.2 N
work done by gravity is 

where 180 is the angle between spiderman weight and displacement
W = -1844.513 J