Get premium membership and access questions with answers, video lessons as well as revision papers.
zo = 10 m and vo = 1.5 m/s; z = 2m, v = ?
v/1.5 = (2/10)0.15 = 0.7855
v = 0.7855 x1.5 = 1.18 m/s
jim items answered the question on April 9, 2018 at 18:00
- A wheel and axle is used to raise a load of 140N by a force of 20N applied to the brim of the wheel. If...(Solved)
A wheel and axle is used to raise a load of 140N by a force of 20N applied to the brim of the wheel. If the
radii of the wheel and axle are 70cm and 5cm respectively, calculate the mechanical advantage, velocity
ratio and efficiency of the system.
Date posted: April 9, 2018. Answers (1)
- . A driving gear having 25teeth engages with a second gear with 20teeth. A third gear with 30 teeth on the
same shaft as the...(Solved)
A driving gear having 25teeth engages with a second gear with 20teeth. A third gear with 30 teeth on the
same shaft as the second one engages with a fourth gear having 60teeth. Find:
a) The total velocity ratio of the system.
b) The mechanical advantage of the system if its efficiency is 85%.
Date posted: April 9, 2018. Answers (1)
- A man uses an inclined plane to lift a 81kg mass through a vertical height of 1.0m. Given that the angle of
inclination of the...(Solved)
A man uses an inclined plane to lift a 81kg mass through a vertical height of 1.0m. Given that the angle of
inclination of the plane is 300 and its efficiency is 75%, determine:
a) The effort needed to move the load up the inclined plane at a constant velocity.
b) The workdone against friction in raising the mass through the height of 1.0m.
Date posted: April 9, 2018. Answers (1)
- A machine whose velocity ratio is 8 is used to lift a load of 300N. The effort required is 60N. calculate:
a) The mechanical advantage of...(Solved)
A machine whose velocity ratio is 8 is used to lift a load of 300N. The effort required is 60N. calculate:
a) The mechanical advantage of the machine.
b) The efficiency of the machine.
Date posted: April 9, 2018. Answers (1)
- An effort of 250N raises a load of 900N through 5m in a machine. If the effort moves through 25m, find:
a) The useful workdone in...(Solved)
An effort of 250N raises a load of 900N through 5m in a machine. If the effort moves through 25m, find:
a) The useful workdone in raising the load.
b) The workdone by the effort.
c) The efficiency of the machine.
Date posted: April 9, 2018. Answers (1)
- A machine requires 6000J of energy to lift a mass of 55kg through a vertical distance of 8m. Calculate its efficiency.(Solved)
A machine requires 6000J of energy to lift a mass of 55kg through a vertical distance of 8m. Calculate its efficiency.
Date posted: April 9, 2018. Answers (1)
- A person of mass 40kg runs up a flight of 50stairs each of height 20cm in 5 seconds. Calculate:
a) The workdone.
b) The average power of...(Solved)
A person of mass 40kg runs up a flight of 50stairs each of height 20cm in 5 seconds. Calculate:
a) The workdone.
b) The average power of the person.
Date posted: April 9, 2018. Answers (1)
- A person of mass 60 kg climbs 3 m up a rope in 20 seconds. Find the average power developed by the person.(Solved)
A person of mass 60 kg climbs 3 m up a rope in 20 seconds. Find the average power developed by the person.
Date posted: April 9, 2018. Answers (1)
- A body of mass 12kg is pulled from the rest with a constant force of 25N. The force is applied for 5.0s.
Calculate:
a) The distance...(Solved)
A body of mass 12kg is pulled from the rest with a constant force of 25N. The force is applied for 5.0s.
Calculate:
a) The distance travelled
b) Workdone on the body.
c) The final kinetic energy of the body.
d) The final velocity of the body.
Date posted: April 9, 2018. Answers (1)
- A spring of spring constant 25N/m is stretched such that its length increases from 2cm to 20cm. calculate
the amount of workdone on stretching the...(Solved)
A spring of spring constant 25N/m is stretched such that its length increases from 2cm to 20cm. calculate
the amount of workdone on stretching the spring.
Date posted: April 9, 2018. Answers (1)
- A crane is used to lift a body of mass 30kg through a vertical distance of 5.0m.
a) How much work is done on the...(Solved)
A crane is used to lift a body of mass 30kg through a vertical distance of 5.0m.
a) How much work is done on the body?
b) What is the potential energy stored in the body?
c) Comment on the two answers above.
Date posted: April 9, 2018. Answers (1)
- A force of 40N is applied on a body. The body moves a horizontal distance of 7m. Calculate the work done on the body.(Solved)
A force of 40N is applied on a body. The body moves a horizontal distance of 7m. Calculate the work done
on the body.
Date posted: April 9, 2018. Answers (1)
- State possible ways of reducing friction(Solved)
State possible ways of reducing friction
Date posted: April 9, 2018. Answers (1)
- Explain why a magnetic material is attracted by a magnet(Solved)
Explain why a magnetic material is attracted by a magnet
Date posted: April 9, 2018. Answers (1)
- State the limitations of friction(Solved)
State the limitations of friction.
Date posted: April 9, 2018. Answers (1)
- State the advantages of friction(Solved)
State the advantages of friction
Date posted: April 9, 2018. Answers (1)
- A bullet of mass 2g travelling horizontally at 20m/s embeds itself in a block of wood of mass 990g suspended from a light inextensible...(Solved)
A bullet of mass 2g travelling horizontally at 20m/s embeds itself in a block of wood of mass 990g
suspended from a light inextensible string so that it can swing freely. Find:
The velocity of the bullet and block immediately after collision.
Date posted: April 9, 2018. Answers (1)
- A 5kg mass moving with a velocity of 2m/s collides with a 2kg mass moving at 7m/s along the same line.
If the two masses...(Solved)
A 5kg mass moving with a velocity of 2m/s collides with a 2kg mass moving at 7m/s along the same line.
If the two masses join together on impact, find their common velocity if they were moving:
a) In opposite directions.
b) In the same direction.
Date posted: April 9, 2018. Answers (1)
- . A bullet of mass 20g is shot from a gun of mass 20kg with a muzzle velocity of 200m/s. if the bullet is
30cm...(Solved)
A bullet of mass 20g is shot from a gun of mass 20kg with a muzzle velocity of 200m/s. if the bullet is
30cm long, determine:
a) The acceleration of the bullet.
b) The recoil velocity of the gun.
Date posted: April 9, 2018. Answers (1)
- Differentiate between elastic collision ana inelastic collision(Solved)
Differentiate between elastic collision ana inelastic collision
Date posted: April 9, 2018. Answers (1)