Answer:
B.The force of friction between the block and surface will decrease.
Explanation:
The force of friction is given by

where
is the coefficient of friction and
is the normal force.
When the student pulls on the block with force
at an angle
, the normal force on the block becomes

and hence the frictional force becomes
.
Now, as we increase
,
increases which as a result decreases the normal force
, which also means the frictional force decreases; Hence choice B stands true.
<em>P.S: Choice D is tempting but incorrect since the weight </em>
<em> is independent of the external forces on the block. </em>
Answer:
(a) The ratio of turns in the primary and secondary coils of her transformer is 1.833
(b) The ratio of input to output current is 0.55
(c) To increase the output voltage, you can either increase the number of turns in the secondary coil (step-up) or increase the input current. Therefore, the Chinese person has to increase the input current of the transformer to achieve an increased output voltage that can power her 220 V appliances.
Explanation:
Given;
input voltage,
= 220 V
output voltage,
= 120 V
General transformer equation is given as;

where;
Np is number of turns in the primary coil
Ns is number of turns in the secondary coil
Is - is the secondary current or output current
Ip - is the primary current or input current
(a) The ratio of turns in the primary and secondary coils of her transformer;

(b) The ratio of input to output current;

(c) To increase the output voltage, you can either increase the number of turns in the secondary coil (step-up) or increase the input current. Therefore, the Chinese person has to increase the input current of the transformer to achieve an increased output voltage that can power her 220 V appliances.
Answer:
TO answer this question i need wave speed
Explanation:
Answer:
599 meters is the answer rounded to the nearest whole number and 599.489795918 meters is the complete answer
Explanation:
to find gravitational potential energy you multiply mass x acceleration due to gravity (always 9.8 on earth) x hight
since we know the gravitational potential energy and want to find out the hight, we take the gravitational potential energy (470,000) and divide it by the product of acceleration due to gravity x mass (9.8 x 80)
so how high the hiker climbed is equal to 470,000 divided by (9.8 x 80)
hight = 470,000 / (9.8 x 80)
hight = 470,000 / 784
hight = 599.489795918 meters
as for rounding, if the decimal is less than 5 you round "down" and keep the current whole number, if the decimal is 5 or greater you round "up" and add 1 to get your new number