Question

1. A mass of 9.9 kg is resting on a horizontal surface without friction. A force is applied vertically upward to the mass. What does the amount of this force need to be in order to begin to pull the mass off the surface, in Newtons?

2. A mass of 8 kg is resting on a horizontal surface without friction. A force of 143 Newtons is applied in the +x direction, a force of 19 Newtons is applied in the -x direction, and a force of 11 Newtons is applied in the -y direction (downward). What is the acceleration of the mass in m/s2? If in the -x direction, include a negative sign.

Answer #1

1.

Given mass m=9.9kg

Force F required to pull the object vertically upwards

F=mg = 9.9 *9.81

= 97.119 N

ANSWER : F = 97.119 N

2.

Given Mass = 8kg

Force = mass * acceleration

First ,Find vertical and horizontal forces acting on body

Fx = 143 -19 = 124 N (force 19N is in -x direction)

Fy = -11-mg = -11 -8*9.81 = -89.48 N

Since there is no friction between object and surface ,no need of Fy

Fx = m*a

accleration = Fx/m = 124/8 = 15.5 m/s^{2} (+ve x
direction )

ANSWER : a= 15.5m/s^{2}

A mass of 2 kg is placed on a horizontal surface with a
coefficient of kinetic friction of 0.3. A force is applied
vertically downward to it and another force of 85 Newtons is
applied at 18 degrees below the horizontal. As it moves 9 meters in
the +x direction it loses 160 Joules of kinetic energy. What is the
amount of the force which is applied downward in Newtons?

A mass of 10 kg is travelling over a horizontal surface with
friction and the coefficient of kinetic friction is 0.53. One
additional force of 27 Newtons is applied to it in the +x direction
(parallel to the surface). It slides 3 meters in the +x direction.
What is the work done by the weight force in Joules?

A mass of 6 kg rests on a floor with a coefficient of static
friction of 0.95 and coefficient kinetic friction of 0.30. One
force is applied vertically downward of 22 Newtons and another
force is applied at an angle of 28 degrees below the horizontal.
Calculate what the magnitude this force needs to be in order to
begin to move the mass. If that force is removed and another force
is applied at an angle of 28 degrees above...

A 2.60 kg block is initially at rest on a horizontal surface. A
horizontal force ModifyingAbove Upper F With right-arrow of
magnitude 6.59 N and a vertical force ModifyingAbove Upper P With
right-arrow are then applied to the block (see the figure). The
coefficients of friction for the block and surface are ?s = 0.4 and
?k = 0.25. Determine the magnitude of the frictional force acting
on the block if the magnitude of ModifyingAbove Upper P With
right-arrow is...

A mass of 1.78 kg is initially at rest upon a horizontal
surface. An applied force of 16.4 N i then acts on
the mass. If the coefficient of kinetic friction regarding the
system is 0.479, what is the magnitude of the object's
acceleration?

A solid disk with a c of 1/2, mass of 2 kg, and radius of 1.5
meters lies on a horizontally (so the normal force and weight can
be ignored). A force of 8 Newtons is applied 0.2 meters directly to
the right of center in the +x direction, a force of 20 Newtons is
applied 0.7 meters directly below of center in the +x direction,
and a force of 7 Newtons is applied at the edge of the disk...

A 10 kg box was lying on a smooth surface. A
rope was connected to the box. The box was pulled by the rope at
angle of 30° with the
horizontal. What applied force will keep the box
moving upward at a constant speed?
A 10 kg box was resting on an inclined rough
surface, which makes an angle of
30° with the horizontal. The
coefficient of kinetic friction between the surface and the box is
0.4. The box was...

A 1 kg mass is on a horizontal frictionless surface and is
attached to a horizontal spring with a spring constant of 144 N/m.
The spring's unstretched length is 20 cm. You pull on the mass and
stretch the spring 5 cm and release it.
What is the position of the mass at 15 seconds? What is the
magnitude of its velocity at that instant?
The mass spring system is now flipped vertically such that
gravity must be included in...

7) A block of mass m1 = 38 kg on a
horizontal surface is connected to a mass m2 =
21.6 kg that hangs vertically as shown in the figure below. The two
blocks are connected by a string of negligible mass passing over a
frictionless pulley. The coefficient of kinetic friction between
m1 and the horizontal surface is 0.24.
(a) What is the magnitude of the acceleration (in
m/s2) of the hanging mass?
Answer: m/s2
(b) Determine the...

The 50-kg crate is resting on an inclined plane 15 deg. with
respect to the horizontal. The coefficient of static friction is
0.2 and coefficient of kinetic friction is 0.15. If a force P,
acting upward and parallel to the inclined plane is applied to the
crate, determine the resulting acceleration of the crate if
P=150N.

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 17 minutes ago

asked 43 minutes ago

asked 43 minutes ago

asked 52 minutes ago

asked 56 minutes ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago