Exhibit 24

                          LIMITED POWER OF ATTORNEY FOR
                          SECTION 16 REPORTING PURPOSES

        Know all by these presents, that the undersigned hereby makes,
constitutes and appoints Kimberly Burke and Carrie Kane, acting individually, as
the undersigned's true and lawful attorneys-in-fact, with full power and
authority as hereinafter described on behalf of and in the name, place and stead
of the undersigned to:

        (1) execute for, and on behalf of, the undersigned, in the undersigned's
capacity as an officer, director and/or 10% beneficial owner of Novocure Limited
(the "Company"), Forms 3, 4, and 5 in accordance with Section 16(a) of the
Securities Exchange Act of 1934 and the rules and regulations promulgated
thereunder (the "Exchange Act");

        (2) seek or obtain, as the undersigned's representative and on the
undersigned's behalf, information on transactions in the Company's securities
from any third party, including brokers, employee benefit plan administrators
and trustees, and the undersigned hereby authorizes any such person to release
any such information to any attorneys-in-fact and further approves and ratifies
any such release of information;

        (3) do and perform any and all acts for and on behalf of the undersigned
that may be necessary or desirable to prepare, complete and execute any such
Form 3, 4 or 5, and any amendments thereto, or other required report and timely
file such Forms or reports with the United States Securities and Exchange
Commission, the New York Stock Exchange and any stock exchange or similar
authority as considered necessary or advisable under Section 16(a) of the
Exchange Act; and

        (4) take any other action of any type whatsoever in connection with the
foregoing which, in the opinion of such attorneys-in-fact, may be of benefit to,
in the best interest of, or legally required by, the undersigned, it being
understood that the documents executed by such attorneys-in-fact on behalf of
the undersigned pursuant to this Limited Power of Attorney shall be in such form
and shall contain such terms and conditions as such attorneys-in-fact may
approve in such attorney-in-fact's sole discretion.

        The undersigned hereby gives and grants to each such attorneys-in-fact
full power and authority to do and perform any and every act and thing
whatsoever requisite, necessary, or proper to be done in the exercise of any of
the rights and powers herein granted, as fully to all intents and purposes as
the undersigned might or could do if personally present, with full power of
substitution or revocation, hereby ratifying and confirming all that such
attorneys-in-fact, or such attorneys-in-fact's substitute or substitutes, shall
lawfully do or cause to be done by virtue of this power of attorney and the
rights and powers herein granted.

        The undersigned hereby acknowledges that (a) the foregoing
attorneys-in-fact are serving in such capacity at the request of the
undersigned; (b) this Limited Power of Attorney authorizes, but does not
require, each such attorneys-in-fact to act in his or her discretion on
information provided to such attorneys-in-fact without independent verification
of such information; (c) any documents prepared and/or executed by any
attorneys-in-fact on behalf of the undersigned pursuant to this Limited Power of
Attorney shall be in such form and shall contain such information and disclosure
as such attorneys-in-fact, in his or her sole discretion, deems necessary or
advisable; (d) neither the Company nor any attorneys-in-fact assumes (i) any
liability for the undersigned's responsibility to comply with the requirements
of the Exchange Act, (ii) any liability of the undersigned for any failure to
comply with such requirements or (iii) any obligation or liability of the
undersigned for profit disgorgement under Section 16(b) of the Exchange Act; and
(e) this Limited Power of Attorney does not relieve the undersigned from
responsibility for compliance with the undersigned's obligations under the
Exchange Act, including, without limitation, the reporting requirements under
Section 16 of the Exchange Act.

        This Limited Power of Attorney shall remain in full force and effect
until the undersigned is no longer required to file Forms 3, 4, and 5 with
respect to the undersigned's holdings of, and transactions in, securities issued
by the Company, unless earlier revoked as to any attorneys-in-fact by the
undersigned in a signed writing delivered to such attorneys-in-fact.

        IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to
be executed as of this 4th day of January, 2017.

                                        /s/ Todd  Longsworth
                                        ----------------------------------------
                                                         Signature

                                        Todd Longsworth
                                        ----------------------------------------
                                                         Print Name