Answer:
B.) a wheel and axle and a lever
Explanation:
P.S - The exact question is -
Given - A wheelbarrow can be used to help lift a load, such as a pile of dirt, and then push the load across a distance. A man pushes a wheelbarrow.
To find - Which simple machines make up a wheelbarrow?
A.) a pulley and an inclined plane
B.) a wheel and axle and a lever
C.) a pulley and a wheel and axle
D.) a lever and a wedge
Proof -
The correct option is - B.) a wheel and axle and a lever
Wheelbarrows are used to carry more goods from place to place by using minimal force as compared when goods are carried by hand.
With this machine, During hauling people can save time.
Answer:
Explanation:
We shall convert the displacement in vector form using unit vector i and j
consider east as x axis and north as y axis
170 km at 68.0° east of north
D₁ = 170 sin68 i + 170cos 68 j
= 157 i + 63.68 j
230 km at 36.0° south of east
D₂ = 230 cos36 i - 230 sin 36 j
= 186 i - 135.2 j
Resultant Displacement = D₁ +D₂
= 157 i + 63.68 j + 186 i - 135.2 j
= 343 i - 71.52 j
Resultant magnitude
= √ ( 343² + 71.52²
= 350 km
Angle
= tan⁻¹ ( - 71.52 / 343 )
12⁰ south of east .
A :-) F = mv^2 by t
Given - m = 10 kg
r = 10 m
v = 10 m/s
Solution -
F = mv^2 by t
F = 10 x 10^2 by 10
F = 10 x 100 by 10
( cut 10 and 10 because 10 x 1 = 10 )
F = 100 N
.:. The centripetal force is 100 N
Latent heat fusion(l)=540
∆t= temp(100-0)
Q=ml+ms∆T
Q=500.100+100.1.100
Q=64000 cal
